Crazy ass feelings!

Ok so I dk wth is going on with me lately.. on Saturday my husband and I had intercourse and right after I started feeling nauseous, cramps, diarrhea, and just felt like crap! The next morning I woke up feeling again like crap! Nauseous, vomiting (only water) so I stayed laying in bed all morning around 5pm I felt just fine, just my stomach a little off but nothing too bad! Sunday I felt fine but Monday around 10pm again I started again with diarrhea, nauseas, and bloating and then went away! Today (right now at 1:52 am) I feel like crap again! I have a lot of heart burn, nauseas, bloated, consitpated, and confused weather I need to puke or go to the restroom! I took a pregnancy test and came back negative! And nobody in my house is sick! Only I am! Help!!! Any thought? Should I go to the dr? Anybody else experience this before? I start my period on the 9 I believe