cramping??

Hello, so I just took a preg test yesterday, the day AF was supposed to be here. Needless to say I got a BFP. Glow says I'm 3 weeks 5 days. But I feel really crampy-- almost like I'm in the middle of my cycle. It comes and goes it's not on either side, but more so in the middle. I feel silly because this is my second pregnancy and I should know. But honestly I wasn't really trying for my first one and therefor didn't know I was pregnant until 6 weeks, so I can't remember what I felt like in the weeks prior. I work in an OB office, so I'm gonna ask one of the docs I work for if I can get a beta drawn, and possibly progesterone levels (I recently had a problem with them and was on Provera for a few months). But does any one have any words of advice or encouragement?