Cramping on one side

I just found out I'm pregnant. I'm either 4 w or 8 w not sure exactly due to a weird period last month which could have been implantation. So I've been having cramping mild, pretty much on the left side with occasional twinges on the right. My obgyn is not likely to fit me in soon, but idk if I should wait or go to the er. I hate to use medical resources when I'm over acting. Just not sure what to do. I've also had 3 mcs and a blighted ovum.