Just Yesterday, When I Stood Up And Took One Step

Just yesterday, when I stood up and took one step forward, a pain occurred, seemingly behind the pubic bone. Since then, when I sit for even a short time, I feel no pain but when I stand and either walk or put weight on one foot or the other, the pain comes again and continues for as long as I walk. During the night, last night, a sharp pain in the same area woke me up. There is no pain when I stand up from sitting, only when I move or put weight on my feet. I have no trouble urinating or bowel movements. This pain came on suddenly and I'm wondering what may be the problem. YYYY@YYYY Thank you