I fell on my wrist the day after carpel tunnel surgery and today when i took off the bandage it looks like dark dried blood under the skin below the i?

Best call surgeon: Doesn't sound like the fall was serious since you didn't fracture anything or go to the er from your description. You may wish to call your surgeon and go in just to make sure you break any sutures or cause any other damage but i think ultimately, you'll likely be fine. Still, never hurts to check in with the person who fixed you up in the first place! cheers!