Stomach pain 4 weeks pregnant

September

I want to know if anyone has felt this way before and if it's just a pregnancy thing. I didn't have it with my first so it's making me nervous.

Lately after eating I get allot of pain in my stomach. It feels like I'm super full in a way although I've only ate a bit and the pain travels to my back. I'm only slightly nauseous but the stomach pain is really bad