my nose usually bleeds when someone hits me or its super cold but not like that wtf
what do you pick your nose with, a chainsaw?????
Could be the humidity drying out his nose a lot. This means that the bogeys that form in your nose (which are just dried mucous) cling really tight to the walls of the nose, and when they're dislodged, by picking, or rubbing, sneezing, being hit or just from general movement, they can pull off bits of the skin, which can cause bleeding.
Could also be an infection that causes the drying, or your Air Conditioning.
You can bleed for extensive periods, such as 20 minutes+, for a number of reasons.
It could indicate you have high blood pressure.
It may also be because you have an issue with blood clotting, like haemophilia, and bleed profusely.
You may be on a blood-thinner, like Aspirin or Warfarin, which prevents you from clotting effectively.
Excessive nosebleeding may cause anaemia if over a long time (meaning multiple frequent nosebleeds)
NHS Choices - Nosebleed NHS Choices - Nosebleed TreatmentNHS Choices - Nosebleed Causes (Take with a pinch of salt, this includes even the most unlikeliest of causes, such as a tumour).