QuestionWhy are there bumps under the glans of my penis? I don't know if I should go to the hospital or not. Can you masturbate too much?
You didn't give me enough information to give you an accurate answer. Assuming that the bumps are on the bottom edge of the glans and in a row, then you probably have pearly penile papules. I described this to another reader in more detail earlier. Click here to read that answer. The answer also includes links to medical pictures so that you can compare it to what you see on your own penis.
In regards to your second question, just about anything can be done to excess. Because the brain is rewiring itself for adulthood, many teenagers are susceptible to compulsive behaviors. For most, the compulsions are mild: you want certain things done in a certain way. But for a few the compulsions get out of hand. I've read about teenagers who constantly wash their hands to the point that they are raw. One boy in England had a compulsion to spray on deodorant to the point that he asphyxiated on the spray in his small bathroom and died.
Orgasms trigger strong responses in the brain and it is possible to become "addicted" to the pleasurable feeling. Add that to compulsive behavior and you have a recipe for a mess. I have read about boys who masturbated so often that they rubbed their penises raw. That is obviously too much.
Of greater concern is that many boys dwell upon sinful ideas to arouse themselves for masturbation. Jesus made it clear that thinking about committing a sin, such as fornication, is just as wrong as actually do so. "But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart" (Matthew 5:28). You can read more about the danger of lustful thought in "What is Lust?"