Cello fingertip injury, please advise?

I have been playing cello for 11 or so years. Last fall I was practicing 2-3 hours a day when all of a sudden I got a sharp pain in my left first fingertip, similar to a pinprick. There was no mark but after waiting a few days the problem hadn't gotten any better. A month later I tried again, and then every month or so since then. It has now been around 8 months and my finger still bothers me a bit when I try to play, although not nearly as much as it first did. Does anyone have any experience with something like this? If so, is it going to recover completely? And how long should I wait? I saw a hand doctor over the winter but he did not know much about instrument injuries and told me I had tweaked a nerve and just needed to wait a few months and it would be fine. Obviously that has not been the case. Any advice would be very much appreciated. Thanks!