I made inquiry while in Tioman last year. They said about 1 week. Is that the fastest already? They said we can't dive just like that. The water pressure below sea level is very great. Some people will have blood come out from the nose. Is that true? This scare me....
Nose bleeding only when you did not do a proper equalize when descending. When I had my first dive, I was too eager to descend and never equalize properly and my nose start bleeding. Don't worry is nothing serious, is just that you have to abort the second dive. The reason why my nose bleed is that I equalize to hard and one of the tiny blood vessel broke that causes the nose bleed.
Just follow instructions and you will do fine.