Wow, that young and hip replacements?
I wonder what caused your hip problems?
Back to answering your questions ~
Funny thing, all parts of the body affect other parts.
Grrr...not so fun!
I think that may be all that is going on. For me, I know that I compensate for pain by over-use of other muscles and it creates a great deal of tissue tension and secondary pain. But no worries, there are things you can do or get done to help and even get rid of the pain in many cases.
I recently had sciatic nerve pain that caused great pain my leg just below my hip socket....normally a strange place to get sciatic pain, for me. I'm not saying your problem is exactly like mine as it never is, but that perhaps your leg is reacting to the stress it has been under, sort of like a spring that has sprung.
I was in so much pain I could barely put weight on my right leg. I was in an accident years ago that damaged my left leg, and I compensate by depending on the right side of my body. This stresses out the right side of my body and it can get locked up and stiff and painful, even though I do stretches, etc. Regularly I need to get help from a massage, chiropractor or physical therapy for releasing the bound up ligaments,muscles, etc.
This time the pain started with hamstring pain in the ligament that goes down and under the heel. It really was painful when I stretched my toes upward, almost shockingly painful. A friend with MS (and the normal MS ligament problems) told me to just keep stretching and the pain would go away eventually. So I did and yes it lessened.
My whole right side was tight and locked up. I had extreme stiffness and a lot of pain from my neck to my toes on the right side. Hot water helped, and so did Motrin, but what helped me most was getting a reflexology Chinese type of massage, and the muscles and all relaxed so my body energy was released to flow more normally. This was done by using pressure points and very gentle massage. I walked out with no hamstring or sciatic nerve pain.
Two days later, I can feel the tension building, so I am keeping up the gentle stretches and sitting straight with both feet on the floor...which is hard for me to do. I feel like curling up. But it I have to work at keeping my body limber and flexible.
Since your pain area is likely in a different place than mine, I suggest that you use hot moist compresses, and do gentle stretches, and gently massage the area yourself. If you can, get a professional reflexology-Chinese whole body massage.
let me know how you are doing with it.