Why arent I losing weight?

Im 14 and short. Like 5'1". i use to weigh 130 pounds when i was 12 but know im 102. The lowest ive ever been is 96 and that was in about january. I wouldnt say im thin i would say im about average but im trying to loose more fat and get more defined around my stomach and chest area. I run for 50 minutes EVERY DAY. occasionally ill skip running for a day. I also workout regularly like 4 or 5 times a week. Im also not too far into puberty so im assuming that might have to do with it a little? My diet usually consists of grilled chicken, turkey breast, lean cuisines, peanut butter sandwich (the bread i use is wheat, 45 calories per slice and i barely put any peanut butter on the bread) and thats about it. I also eat subway turkey sandwiches and chick fil-a chargrilled chicken sandwich. I drink propel zero and occasionally diet soda. Im not really seeing any results in the mirror so i wouldnt say im staying neutral by gaining muscle and loosing fat because it sure doesnt seem like it.