I am a 59 year old woman 5 6 138 pounds, active, walk 1-3 miles nearly every day, some swim and gym work on elliptical machine, some free weights . . . am healthy . . . no meds. But recently when walking, if I suddenly move forward quickly as if initiating a run, it feel an intense pain in my right hip, almost feeling like it is out of place for a second or two. I try to walk through it and it passes in a very short time, but it does stop me in my tracks and is happening more frequently. What is this, please?