What should I do to my finger after accidentally smashing it? Its bleeding a bit

Clean/Elevate. If this is minor, clean it with soap and water and apply some antibiotic ointment and wrap it and then elevate it above the level of the heat. A cold pack will help with swelling and pain. Make sure you are up to date on tetanus immunization and observe. If redness, pus, streaking, fever or such, get seen. If you suspicion you broke it, get seen. If loss of function of finger get seen too!
Have it seen by doc. A smashed finger may involve a fracture of the bone and if there is bleeding this may require some special cleaning. If the nail has been traumatized it may need repair.