Injury... but it was more tendon strain than nerve damage.

I didn't feel it at the time, since I banged my knee...so in a couple of days the knee got better, then I continued exercising and working and about 6 wks later
the tendon blew out.

We had just arrived on vacation in a remote place with little medical service.
So I lived with it, stayed in bed, couldn't move my leg at all for 7 days, and the pain was indescribable.

When we got home I was sent to PT and they thought I ripped the tendon off my pelvis. After 3 treatments with IFC electro stim and ultrasound, I started to get less pain. I went for 3 mos to PT and slowly the pain faded...to a dull roar,
and now I don't have much except on exertion. I am not as flexible as before
however. I tire easily walking and have some lower back weakness on that side still (after 2+yrs.) It took forever to get better. I don't expect to ever be back to what I was unfortunately.

But don't discount TENDONS...they take a long time to heal, too. You may have damaged some tendons like I did.
I used Lidoderm patches with success. And Flexeril at night. But the doctor would not give me narcotics. Some days I need an Aleve liquigel, but the Lidoderm patches were the best for me. They are very good for nerve pain.

In your case you'd have to experiment a bit on placement. I found putting them on my lower back (sacral area) on that side to be the best location.

I bought an IFC unit to use at home, and that helped too. IFC is better than TENS. It actually stimulates healing.