Weak legs/Poor circulation?

Hey guys. I’m about 4 weeks pregnant and for the past couple week or so I’ve been having what seems like poor blood circulation in my legs causing them to be weak. Just now I was barely able to walk to the bathroom. It’s not a cramping feeling or charley horse. It’s kind of like losing the feeling in my feet if I sit wrong for a few minutes and legs being weak. This happened with my last pregnancy but it was either at the end or right after she was born. Has anyone experienced this so early on?