So, 4 months ago I was in a relationship with a boy, we had, for the first time, protected sex, and my period came just right a week later (my period is irregular, so I started bleeding the day 21st) then, that week I had unprotected sex with him, during my period, he came outside me, and my ovulation day was like 9 days after that. All my periods came right, normal craps, bleeding, but in my last one it got a little bit late, it came the 37 day of the cycle, but for me it was normal, some times it is like that, but this month period didn't came, I'm on the 39 day, I feel like a little bit of craps, and that happends when I'm about to get my period, but it doesn't come down. And of course, I haven't had sex since then, but I'm still a little bit worried, even though I haven't won weight, I hadn't feel bad, or tired or w/e, not hungrier than before, and if I was pregnant wouldn't I have a big BIG tummy by now? (I'm kind of chubby, but not obese). Also, a lot of my female classmates are having a late period too.
What do you think?