Sorry to hear that hon. Best would be to see your GP, maybe you can be refered to a specialist. They can advise you about what you should and shouldn't do, perhaps there is some exercise to try.
Maybe when you lie down, put a pillow btw your legs, that may help to alleviate the pain. Hopefully it just goes away by itself (I had excruciating pain in my hip after pregnancy, but it went away luckily). Sorry, I am not much help. Wishing you the best!