I'm worried...can anyone reassure me?

Sarah
I received a positive pregnancy test 11/29. Went to doc 11/30 and hcg was only 30. 2 days later it was 109, which surprised me. I was so certain I was going to miscarry after already suffering a miscarriage in February and then again in September. I have no children yet, so if this one survives, it will be our first. Last night, I felt light headed, heart was racing and I had trouble catching my breath. Today I am having constant low abdominal cramping. I don't know what a normal pregnancy is supposed to feel like. Is everything ok?