Problems making girlfriend orgasm/squirt?

Been dating my girlfriend for 10 months. Started having sex in the past three months. We're both each other's first. We're both very attracted to each other (I've been in martial arts for 5 years and have a solid body and she's in volleyball) we use BareSkin condoms by Trojan along with lube because we're both 18 and the lube kinda helps her o.o but I can't make her orgasm. At all. I have lasted for 3 hours before and she still couldn't have one x.x any tips/advice? Please? PLEASE? Lol thanks.