Try not to stress about it.

With my son's pregnancy my BB's started to feel completely normal again at about the same stage you are at now. They never really got sore again. I never got what I would call MS during the pregnancy - yet I was still pregnant. I remember feeling really worried - I'd already had 3 losses at the 5 week mark & just thought "here I go again" but it was not the case. I seriously felt very "normal" throughout much of the pregnancy.

I wouldn't worry about seeing a doctor unless you get spotting. That was always the first sign for me that a loss was imminent, but even then I had two lots of that with the last pregnancy & it meant absolutely nothing.