Well its looks like Im a newbie here. Hello everyone. I'll start my first post with a style question I have for you. I am 15 years old, I stand 5' 7, and weigh about 140. I work out frequently and have muscular build. Most of the time Ive been a teenager I have worn my tshirts in a size S. Sometimes I feel this may be too tight, but when I try M's I feel they are too big. Is this just because I am not used to that size or should I still with the small? A lot of people say I look good with the small shirts but others say I need to get them bigger. If anyone has any advice it would be greatly appreciated.