I fell in the street and now my left palm is pretty cut up. Advice?

[nanana]

So I fell in the street biking and I caught myself with my palms. My left palm is cut up and in the center there seems to be a really dark color. Almost black. I'm not sure if it's a bruise or me bleeding and the blood can't get out because there's skin in the way. I'm pretty sure it isn't gravel. I'm seeing a doctor tomorrow but in the mean time wanted some advice