not sure of pregnancy

I have sooooo many symptoms of pregnancy but every test that I take comes back negative. I have nausea, sore breasts, cravings, sensitivity to smells, cramping in my lower abdomen as well as swelling (it looks like I'm about three months right now) I have trouble fitting into my clothes but I don't want to jump the gun and go buy maternity clothes. On top of that I have diarreah which I hear is also an early sign of pregancy but often times not a good one. I was told it may be a sign of misscarriage. I've taken at home tests as well as been to the doctor, and I'm stessing over this. Has any one else had these kind of things go on and had a negative test or a positive test later? Just want to know what are my chances!

Hopeful
mommi1