4 weeks pregnant, cramping...

I'm cramping pretty good. It seems to go from one side to the next and sometimes it goes from the side to the middle. It almost feels like it gets tight then releases. Then it's gone for a while. Every now and then it feels like it almost goes into my leg. By no means is it unbearable, just very uncomfortable and Def noticeable. Is this bad? I miscarried in June so I'm very nervous.