Boob talk (TMI)

Hi, this might be kinda TMI but I am seriously confused/worried. I am 18 & sexually active with my boyfriend. We usually use condoms but sometimes we forget or get caught up in the moment. Lately I've noticed my right boob is quiet a bit smaller than my left, as well as my nipple & areola are different than the other as well. Does anyone know what this could mean? Hopefully not pregnancy, I'm just lost. Thank you!!