He might have musked you, which is a good sign as he would need to have control over that area to actually musk. I would leave him alone for awhile, keep him in a dark warm place with water, and see how he does. The less stressed he is, the best possible chance for recovery.
I had a similar thing happen to a house gecko I found. He/she had gotten partially stuck in my door and couldn't move his rear legs. I kept him warm in a kritter keeper for a week or so, with some water. By the end of the week, he was moving quite well, and by the end of 2 weeks, he was able to use his legs, so I let him go. He/ she scrambled right up the side of our house.
Just see how he does. If you notice any bad smells, signs of redness or infection, then I would definitely euthanize him.