Nose bleed for the first time left nostril headache on the left side, little dizziness. what shall i do?

Nose bleed : Put a lot of ointment in the nose that bled. Usually nose bleeds will stop when you humidify the nose. Irrigate the nose with saline 50 cc each nostril 5 times a day. Use ocean nasal spray throughout the day. I would not worry about the dizziness. This probably occurred because you were scared about the nose bleed and hyperventilated. Good luck. Feel better!