Pinching in lower abdomen?

I realize that it's probably all in my head and probably not even possible because I JUST got off my period on Thurs night/Fri morning, but glow said my fertile window had opened yesterday, and to start having sex at least every other day, so my husband and I did this morning around 9:30am. Around 5:30 I started feeling like someone was punching the inside of my lower abdomen (left side) right above the hairline. It was only for a maybe 2 minutes and it went away. Felt the same pinching feeling about 20 minutes ago for a couple minutes but it has gone away. Has anyone else experienced this or can anyone tell me what this means? Just started TTC and I don't want to psych myself out.