Bilateral Leg Pain Since Childhood - Seeking Advice

I have had bilateral leg pain since I was a child. Too much walking/standing, too much sitting, or sitting in a weird position will set it off. Other times it’s random. Never both legs have pain at the same time, they switch. Focused mostly on the thigh but it does reach lower leg. Only thing that works is ibuprofen. Anyone have anything similar? I’ve yet to be given a definite diagnosis after all these years.