If i masturbate in a pool does it get all the women pregnant?

No: This just isn't happening. Fresh cool water kills them in minutes. But please don't do it. If anybody at all finds out -- and you never know who's watching -- you'll end up embarrassed and very likely in serious trouble. For your sake, little brother -- this might be a great time to talk with a few sensible adults about your changing mind and body -- maybe even dad.