It sounds like your ligaments and muscles are being stretched! I used to love having a nice bath to relax my muscles. And having plenty water can help. I know it does mean having to get up a few extra times maybe during the night but that way you physically are getting up and moving around enough so that babe' doesn't "tire out" or stretch the muscle in the one spot for a long perios of time.
And if bab' is uncomfortable they'll try move themselves but might not get it right by themselves hence leaving a bit of a tender spot where they've tried to push against you to try move.
Chat to you doc about pain relief though... Maybe try go for a professional massage too.
If it gets any worse or doesn't ease maybe chat to the hospital midwives or doc.