Hi Glitter,
If your incision is in the front, sound like you had direct anterior, where there are usually few, if any, restrictions. I had that approach Oct. 30 & went home with NO restrictions at all, including side/stomach sleeping. Reality was that I couldn't stand to comfortably sleep on the operated side until about 4 weeks out, when the incision tenderness began to abate.
You should check with your OS's office, of course, but sounds like your buttock/groin pain is par for the course. I had it too, at about the same time--it's your muscles finally waking up and protesting being stretched and spread apart during the surgery. My doc didn't prescribe ANY PT, but I found certain stretching exercises that helped. Check with your PT as well.
I think we all want to believe that the only recovery path is straight up until we get to "normal," but in truth, that path meanders up and down a bit. You should, of course check out anything you're worried about with your OS, but otherwise, just go along for the roller coaster ride!