Sooo... Yesterday i read like every post on StackOverflow that explains several possible reasons why my form_validation was always false. In php. It is a project for college so today i asked my teacher to have a look at it. He simply said "cant, no time."
LITTERALY after he let me alone with my code, i find that the variables that were on the form of the html file were all diferent of what was supposed. And after change it back.. it started working.