I too have groin leg and feet pain as well as lower back pain. I have had a chronic bladder infection for years under treatment for 3 years of strong antibiotics. I am under Professor Malone Lee who is doing extensive research on bladder issues. This isn't a regular uti infection this also causes deep internal and kidney pain. Now three years in to treatment and a recent increase in antibiotics again, my calves started to cramp periodically waking me in the night then a deep hot groin pain started, after a few weeks of that, pain then started to radiate to inner then top thighs. For many years I randomly felt the pain in my feet in the mornings but now its all the time, highly painful as if I've walked on a big stone beach. Dr took loads of blood tests all negative. I spoke with Prof who said this is very typical of the bladder condition and has increased antibiotics. Now on Azythromycin and Cefalexin daily. Nothing was helping this pain but a bath and a hot water bottle soothed. Today, 1.5 weeks after increasing meds I can feel a slight relief. I rested all yesterday off my feet 90% and have slight relief this morning.
Maybe google Professor Malone Lee and check if you have any bladder issues.