My somach has been hurting for a week and i feel like throing up?

Since Friday my stomach pains appeared, usualy it would go away after a day, but it's still here and I feel like its only getting worse. I've been feeling like throwing up but I haven't yet, today I couldn't even sleep right because I thought I was going to vomit. It feels like I have that acidy build up in my throat just before vomiting, yet I didn't vomit. It's weird cause I don't think I have dierreah(sp)( althought my stool became water consistency but it keeps changing, one day its passing little stools next day its watery) or constipation. It's really bothering me because I can't focus on my finals or homework. Please help.:-(