Index finger swelling and pain 3 months

[sunnymom2]

For the last three months I have had an issue with my right index finger. At first it seemed like just the middle joint, now it is entire finger. It is noticeably swollen compared to my other fingers. It hurts all the time, but especially if pressed on or accidentally pressed when doing activity like turning door knob,etc. I saw doc over a month ago who did X-rays and said they looked normal. He said cause may be unknown and will subside on own? I didn't mention to him but kind of around same time it began (though not sure how long prior) I did have small cut on finger. I cleaned it, used antibacterial cream and never thought of it since. However now I wonder is it possible to be infected? I do not have or have not had any fevers or felt sick. Now for last few weeks I have lot shooting and stabbing pains in finger when I am not even using it, just sitting and it happens. Quite strong pains like a knife quick stab like along all of finger. Any ideas what this could be or tests? I feel fine other than this issue. thanks.

[sunnymom2]

I should add the original doc along with X-ray did full blood work for R/A, Lyme, and Lupus, all were negative and rest blood work normal. Thanks.