I am an avid bike rider and i crashed about 3 to 4 weeks ago. i thought i had a bruised palm. i am beginning to think it is a broken 4th or 5th metacarpal. i still have full range of motion of my wrist and fingers. it hurts slightly to grip the handle bar

I : I agree you could have a fracture especially if you still have pain. So go get seen as said before it may not be enough just to show up locally nd get an x-ray special views may be needed. With negative films know that bad palm contusions can also take a few months to resolve but rule out a fracture at the base of the metacarpal as you suspect and don't forget about that hamate bone.

You : You may have fractured the hook of your hamate bone deep in the palm. The only way to rule this out is with a special view xray or ct scan. I would suggest seeing a hand surgeon.