My left elbow is slightly swollen and it's hard to move/flex my elbow due to the throbbing pain. there's also a small bump of pus. how do i treat this?

Take it to a Dr.: If there's pus and throbbing, it's an indication of infection. That's better addressed by a provider who can prescribe antibiotics if needed. Cleaning out the wound incompletely would just lead to having to deal with it later - so go to a clinic or your provider. It's a chance to discover the underlying cause (if not an injury) and deal with that too. Best!