Ironically my PMR started in my right hamstring after an 8 mile hike, that felt fine. Like many I attributed it to over doing it for my age. Not so, it was the start of my PMR. Anyway, I’m with the person who thinks your initial dosage might be too low. I started at 20 mg not 15. That did the trick. Talk to your doctor about bumping up your dose. If we have to take prednisone we might as well be pain free while doing it. Keep us posted. Best to you!