I've recently deposited fat under my chest, on stomach, and near my waistline. Is this due to estrogen? Is this normal for a guy in tanner stage 3.7 and age 17? Is this estrogen needed for growth?
All humans produce both estrogens and testosterone. At puberty, males produce drastically more testosterone than estrogen and females produce drastically more estrogen than testosterone.
The distribution of fat that you are describing is typical for males who are eating more calories than they are using. Women tend to put fat first on the hips and breasts.