I do sex with my gf without any protection after 5 or 6 hour she do vomit what is the matter?

Have her checked: She may have urine infection or other issue causing nausea, is not likely sex itself. Both you and her should be checked for diseases. Unless you are ready for a baby, have names picked out, have your career, too much money, too much time, and are sure she's the one to have your child, you should use condoms and another type of birth control.