Ok so I'm 18 I no I'm not prego I haven't had sex in almost 2 years. Well I missed 2 periods and I've been having really bad cramps and my breasts hurt So I was just wondering is this normal or what? Am i going to start soon? Please help me... O BTW I am a little bit over weight and I just started exercising like a week ago. Can this have something to do with it? O and I'm not birth controll.