Stiff joints

Hi I'm 33 weeks and I'm getting incredibly stiff trying to walk. I'll have really bad pains in my hips round just to the top of my bum.

At this point I'm meant to be getting some exercise but I can't not budge, as if my body won't listen to me. Even turning over in bed is painful.

This is my first pregnancy so I'm not sure what is the norm. I am also 4ft 8 if that might be the cause to the amount of pain I'm having?