I don't know if the cramps have gone away or not, but period like cramps are something to at least call your dr about. It's hard to know if stuff like that is ok or could be something wrong without being checked out.
Hopefully you got it figured out, I had the same thing happen to me at 20 weeks, and I was petrified. My uterus was going through what felt like contractions. I talked with my doctor on the phone, as I was in another state, and we decided that it was just round ligament pain. Hopefully that's what yours is, also. She asked me to check if I was bleeding, which was a bit hard to do on the expressway with my husband and 12 year old step son in the car, as well. Thank God I wasn't.