Lower Abdominal Pain and Stomach Distension!

Wednesay, after I ate, I became super uncomfortable, so uncomfortable I had to take off my belt and unbutton my jeans. I became really nauseas, bloated, and I had a lot of pressure and pain under my belly button, it was extremely uncomfortable. This same feeling happens EVERYTIME I eat. It goes away 1-2 hours later though. I fear the worst. I have a history with ovarian cysts but this, this is different. I'm thinking ectopic pregnancy, tumor, cyst, or cancer. I'm terrified. 

I scheduled a ultrasound for Tuesday, Dec 2, will the doctor be able to see what is causing this uncomfortable pressure like feeling after a meal? I'm terrified. I keep thinking "What if?". Does anyone on here have ANY idea on what this could be, I googled it and it comes up with 67 different causes. 

I do not remember feeling like this with my first so I doubt it could be pregnancy. But any advice, ideas, or opinions on what it could be would be greatly appreciated. 

Thanks, love y'all bunches!