Bloody puncture at top of thumb, blood under nail, from a fork. washed immediately, 6 times with soap+alcohol+betadine. how can i tell if infected?

When there's pus: Depending on what was on the fork, and the fact that it's metal, means making sure that you've had a tetanus booster. Also, with the puncture you are going to experience pain and throbbing. So if there's any signs of swelling or inflammation, or the skin is red, it needs medical attention. If it's a deep puncture, and you irrigated and applied soap, you still may need to see a doctor to start oral antibiotics.

Watch: Signs of infection include red streaks, swelling, increased pain, pus, and warmth. It sounds as if you administered good care. If the fork was grossly contaminated with bacteria, the chance of an infection should be low. You should hopefully be up to date on your tetanus status as well. Watch and observe closely. If not improving, go to the er.

Subungual hematoma: If there is a infection there will be redness, pain and pus in the area. The digit may be hot to touch as well. If the bleeding under the nail is very little and there is no pain, nothing needs to be done. But if it is painful then the blood needs to be drained.