I'm a 16 year old male. I'm going through puberty at a slightly slower rate but am not worried. I am a devout Roman Catholic. I am having trouble finding an answer to my question, as I am too embarrassed to directly ask a priest and online sources only offer the secular voice. Here's my problem:
Since I was about 9 or 10 I masturbated, not realizing this was a sin (as taught by my Church and with which I agree). One time when I was 14 I was masturbating and reached an orgasm. I knew at this point that masturbation was a sin, but the experience was so pleasurable that I began to masturbate much more frequently. I became 'addicted' to porn and masturbation. Through the grace of God I was able to quit both these habits and grow incredibly closer to God. I thought that after this great victory over Satan that I would never go close to my old ways again. However, I recently began feeling excessive sexual excitement during erections. The worst was last night when I was drifting between sleep and wake, I began to spontaneously masturbate face down upon my bed (without the use of my hands). The whole time I did this I was drifting between my conscious self putting a stop to it, and my sleeping self going back into it. I reached an orgasm and then fully 'woke up' though I was never fully asleep. I felt (and still feel) ashamed and confused. I don't know if this was a sin, seeing as 'dream sex' is NOT considered a sin, while masturbation is. I was thinking about sex at the time, though it was more of a battle of temptation: my awake self putting the thoughts from my mind, my sleeping self entertaining them. I want to know if this experience is normal and if it is a sin.
The Roman Catholic church teaches that any conscious act of sex not done for the purpose of attempting to conceive children in a marriage is a sin. They word it carefully so that wet dreams are excluded because they are not done consciously. They also exclude children playing with their genitals as being a sin because they are not aware that this is condemned.
However, it really doesn't matter what the Roman Catholic church believes. What matters is what God says about the matter. It is God's word which defines what is or is not truth. "Sanctify them by Your truth. Your word is truth" (John 17:17). Since it is God who judges (II Corinthians 5:10), and not the Roman Catholic church, we should be concerned sole with God's view of what is right and wrong.
The topic of whether the act of masturbation is a sin is discussed at length in "Is masturbation unacceptable?" So, I won't be repeating the information here. What I find disturbing is that you decided that masturbation was wrong because you reached orgasm. This isn't a valid standard for why something is right or wrong as it is based on personal experience and not on what God declared. Where you and I would definitely agree that the viewing of pornography is definitely wrong. Masturbation doesn't require the use of pornography and people who view pornography do not necessarily masturbate, though frequently the two are used in conjunction. The Bible states, "For this is the will of God, your sanctification: that you should abstain from sexual immorality; that each of you should know how to possess his own vessel in sanctification and honor, not in passion of lust, like the Gentiles who do not know God" (I Thessalonians 4:3-5). The phrase "passion of lust" refers to things, such as pornography or exhibitionism, which are designed to arouse lustful thoughts of sex in a person's mind. I am glad to hear that you broke away from this sinful habit. It is a difficult one to conquer.
The rest of what you describe is normal for a male. Your seminal vesicles continually produce semen, just as your kidneys constantly produce urine. As the seminal vesicles get full, they send out signals that raises your sexual feelings, just as when your bladder gets full you become more aware of the need to urinate. Once a certain point is reached, your body gets rid of the excess semen through a wet dream. This is not a sin; it is the way God designed the male body.
Since ejaculation cannot occur without the body being physically stimulated, your body supplied the stimulation needed. It happens during the R.E.M. phase of sleep. This is the phase when you dream, it is also the phase when men have erections, and it is the phase when those who tend to sleep walk do so. We go through the R.E.M. phase of sleep just before drifting off into deep sleep, when we turn over in our sleep, and just before we wake up. Typically most men enter the R.E.M. phase of sleep about four to five times each night. At any one of these phases it is possible to have a wet dream and ejaculate.
That you were semi-aware of what was happening is also not unusual. It won't happen this way every time, but it does happen from time to time.
I suspect that the confusion over the event is due a misunderstanding of what is right and wrong. Paul warns about making up rules regarding right and wrong. "Therefore, if you died with Christ from the basic principles of the world, why, as though living in the world, do you subject yourselves to regulations -- "Do not touch, do not taste, do not handle," which all concern things which perish with the using -- according to the commandments and doctrines of men? These things indeed have an appearance of wisdom in self-imposed religion, false humility, and neglect of the body, but are of no value against the indulgence of the flesh" (Colossians 2:20-23). In other words, we have this concept that denying ourselves somehow makes us more holy or more religious. Unfortunately, it doesn't work in our struggles against sin. There are many things which God tells us is sinful and that we need to avoid. But we don't improve the situation by adding additional "sins" to what God has already told us. To feel guilty over a natural function of the body is not productive to your spiritual health.