what's going on with my body.

A couple of night ago I had sex. My bad came inside of me. When I went to clean up, I gagged. I have NEVER done this before. Well Monday night I went out with a friend to the bar to play pool. When I got into work the same night I started gagging and I threw up driving (I had no alcohol) the same night I lit a cigarette (gross I know but I am trying to quit and it was my first for 8 ish hours.) I ended up throwing up as soon as I took the first hit. I tried eating some crackers and managed to throw that up as well. So of course I took a pregnancy test, it was negative. I got home from work and threw up as soon as I walked in the door. I went to sleep and took another test when I woke up. I don't have any other symptoms except the throwing up. I don't have a fever or anything. A day went by I felt fine until I got home from work and tried to lay down. When I laid down I threw up again. I don't know what is going on but this doesn't feel like a cold or the flu. (Yes, I have endometriosis stage 4) but I haven't felt like this since I was septic. Does anyone know any home remedies that can help with nausea? And does anyone know what might be going on?