Injury to my knuckle (palm side)...any thoughts?

About 3 weeks ago I fell down the stairs. I was pretty bruised up from head to two and my hand was no exception. I "broke" the fall and thought for a week or so that I had bruised my palm. Now I've noticed that the pain hasn't gone way. I can't grasp things without it hurting, steering my car, etc. I see that the palm, right at the knuckle is swollen and that there is a hard bulge present that is not on my other hand. What could be the cause? Bone fragment? Tendon? Cyst??? I can't imagine it being a cyst as it was the result of a fall. It's odd that there is such a large lump. It's not in my dominant hand so that's a good thing. I'm considering seeing someone but feel a bit foolish cause it's not a huge bother. The flip side to that is that it's not healing and I don't want it to cause joint problems down the road. Considering some Glucosamine and a splint but was curious if anyone had this happen and if I should see a doc and get it x-rayed...

Ms.April