How come some days I look pregnant. and other day I look just fat, or some days I look big and other days my belly is small?

I feel like I miscarried..I had "periods" my whole pregnancy, but the last one was super bad and heavy. Then just a few days ago I started feeling like I have morning sickness and still do. I went in and all they did was a pregnancy test...um, I still don't know if I miscarried and got re-pregnant or if I didn't.

I'm young and pregnant. I keep getting incredibly dizzy and end up falling over a lot of the times. My boyfriend said that I'll have seizures or the beginning of ones. He doesn't know what to do. He's caring but, panics too much.