Suggest Treatment For Painful Legs And Groin Pain After An Injury

about 8 days ago I had gone outside to warm up and stretch before going out to walk -- I was on a deck (wood) and wen t to do a side stretcha nd the leg I was leaning toward slipped out from under me. I am almost 50 and have never done any full split in my life -- well it was about a full split. In the beginning I walked it off -- but felt pain down my legs -- not too much in groin - but almost immediately there was pain -- like a pull in my low back all the way across top of buttocks. now that pain has subsided with rolling on a tennis ball and ice and advil -- now pain and discomfort are mostly in left glutes and down left side of left leg. Currently rolling on a tennis ball two times a day and ice - or heat a couple times of day --- thanks for advice