Missed periods and growing stomach

Okay, This is a long question.

I had my last regular period october 15th 2009, I bled for the normal 8 days heavy and on time. november came, and i didnt get my period on the 15th like it should have been. I waited until the 20th took a test it came back negative. The 21st I had very very light pinkish bleeding, and it was gone by the 22nd. I am in college and I was too far away from a doctor, so I went home during christmas break, and everyone was commenting on how I looked pregnant. I went to make an appointment with my doctor, but he was on vacation, and where I live your doctor is the only one allowed to test you. On the 23rd I had light light pinkish bleeding again, and it was gone by christmas morning. In January I took another test just in case, and once again it was negative. So i figured I cant be pregnant. Well I never got a period or any weird bleeding in January, febuary came, and my stomach was expanding and i was like, okay what the heck.. I called my doctor on the 2nd, apparently he was out of the office until the 10th. So, i figured, i'll wait it out til my college break, I had pinkish bleeding, feb 24th, and its gone now. Well, i am home, and I'm getting really weird fluttering feelings in my pelvis area, so i think i am pregnant, I have an ultrasound march 2nd.. Does anyone else think i'm pregnant or just having a different period..?