Is it all in my head?

Gonna keep it short:

I had a non-hormonal IUD removed on the 25th. My husband and I had unprotected sex on the 27 (my supposed fertile week). Since the 28th I’ve had headaches, strange stomach cramp-like sensations (not how cramping usually feels... it’s a strange stretching feeling) but also slightly nauseous. My stomach also won’t stop acting like it’s hungry when I’m clearly not.

I keep telling myself it’s just in my head, but then I’m out of the house completely distracted & my stomach starts to feel strange again.

It’s obviously too early to test as my period isn’t due until the 13th.

Can anyone else relate?