I haven't but I thought I did when I first found out I was pregnant. Horrible one sided pain. I went to the doctor and they did blood tests to make sure hcg levels were rising appropriately, then I got an early u/s which showed the sac was in my uterus. This happened around weeks 4 & 5. If you think something is weird, definitely go to your doctor and have them check it out.
I still don't know what that pain was that I had starting out. It stopped around week 6.