Newly pregnant and cramping?

I am pretty sure I am pregnant based on the 2 out of 4 positive tests I took and I am concerned abut my cramping. Starting about 2 days ago I began having cramping throughout the day, most of the time just slight twinges but some were just breath-takingly bad. I had a miscarriage before and had the same symptoms before I lost it at 5 weeks. Is this kind of cramping to be expected as the uterus expands or is it abnormal and a sign of miscarriage?