Around 5 weeks ago I got my finger kicked really hard in a fight. I've had it x-rayed and it looks fine apparently but it still hurts like hell constantly and has completely diminished my grip strength. Help. What could it be? 

Is it bruised or swollen? It could just be pain...I mean you did get your finger kicked in. I know from experience that it doesnt always heal quite right.

It was incredibly swollen for 2 days. Now there are no physical differences that I can see. All I know is that it severely hinders my grip. 

If theres no break, then its probably just a little bruised internally and needs some time to heal.
 
Your grip should return to normal soon enough.

Hows it going now? Its been 7 weeks..

Well, it still actually hurts quite a bit still. My bones are wierd because they have an extremely high density (like 1.25 more than the average human) so it takes quite a bit of force to break them (the only thing resembling a broken bone I've ever had is my knee cap fracturing due to falling on a large rock when I was 12). For example, I tried deadlifting overhand style and after 1 rep my grip went down majorly. I also noticed that when I am cold it is in fact discolored, leading me to think it's just badly bruised. Ugh. I guess I have to put it in a splint or something