copper556,
You could have a few things going on in the hip joint. You could have some degenerative changes of the articular cartilage. So, to the thunk, that could be the ball moving over defects of the articular cartilage.
It could also be coming from a snapping hip syndrome. This is caused by some of the tendons around the hip joint being very tight and snapping over each other.
Another problem, not too well known about, but has lately been noted by hip surgeons, is a labral tear or femoralacetabular impingement (FAI). The labrum is a cartilage rim around the outside of the socket (acetabulum), that acts to deepen the socket, making the hip joint more stable. But, it can detach from its attachment or it can tear. Occasionally, the torn labrum can flip into the joint, then the joint has to pop or whatever to get it out. This could be causing the sound and pain.
FAI is often associated with labral tears. It is where the neck of the femur abuts or impinges on the acetabulum. This impingement can cause pain.
Some spine problems can cause pain around the hip region also. Spine problems could also be causing the leg and foot problems.
The foot problems may be associated with the hip, coming from the spine, or they may be independent problems. Muscle spasms in the feet are very common. But, they should be checked out.
Not all physicians are up on all of the hip problems. If the physician does not do a thorough hip, foot, knee, and spine exam, and just says you have arthritis, tendonitis, or bursitis, you may want to see an orthopedic specialist.
Good luck.