I have serious headache when i sing very hard and pitch high. i haven't sang in a while. please could you help.

AttentionToBreathing: Have you had singing lessons?I've heard it's a lot about proper breathing and use of the diaphragm to create the most efficient use of your lungs so that you don't strain too hard to sing high,which can give you a wicked headache.May be related to time of day/night,how much sleep you've had (too much, too little),bright lights,etc. Maybe you don't like your own voice;for that I'd suggest earplugs

Any other times: Do you have this problem other times such as when you sneeze, have a bowel movement, cough? Any morning nausea or headache? If so, you might want to see an MD to make sure the "pressure" in your head is not elevated.