Hi Ness
Yes your pains are normal and caused by things stretching.
Personally I would advise you to wait until 12 weeks until you have your US. As yet US has not been proven safe for baby's. In the past they used to x-ray you to check on your pregnancy, but that was before they knew the harm that x-reys can do. US doe have it's place but I don't think it should be done too often