I have had two total hip replacement about three years ago. I am 42 and very active. I have been having some constant pain for the last week. I have h?

Hip pain. If you're having constant hip pain (w/ history of hip joint replacements) definitely see orthopedic surgeon for evaluation to make sure replacement hasn't come loose or fractured bone or become infected.
Various possibilitie. Among the possibilities are a loose hip components (detachment of the metal from the bone, which may require further surgery), tendinitis (of the gluteus medius), heterotopic ossification, and slow-growing infection. You should probably see your primary physician in order the tests that are necessary to determine what this is.