Is it possible?!?! Help.

Is it possible to ovulate the day after your period? My cycle got a little screwed up. I've been very regular my whole life until I joined the army, they give you a shot that regulates your hormones in basic training so that males and females can train together without sexual hormones. Which surprisingly worked well. Well it had stopped my period completely for three months and when it came back my cycle was crazy, which makes me wonder if that's why I haven't conceived, it may have changed my ovulation times. Since then I regulated back out, this month I started a week early. It ended three days ago, according to glow(which I know is not completely accurate) I'm in my fertile window. Me and my SO have had sex for the past four days just to be safe, tonight I'm having a serious pinching very low in my abdomen. I'm wondering if i ovulated because normally I cramp when I ovulate. Could I ovulate this soon after my period?