completely agreed with CassCore...
There are thousands of reasons why your girlfriend may not have felt pleasure. I will list a couple. If it was the first time the 2 of you had sex she may have been nervous. A woman HAS to be in the right mindset to feel pleasure. If she's thinking about the way her body looks or if it feels good for you or if she's being too aggressive she looses focus on just feeling pleasure. This anxiety typically decreases with time and the more and more comfortable you get with eachother the easier it will be for her. Reassure her that you love her and want her to feel good and not to think so much, just feel. Also, if she was a virgin it could have been painful for the first time. Try using lubricant or foreplay to warm her up. Also certian positions are less pleasureable for the woman. Have her try being on top or in a position where you can rub her clitoris. The stimulation of her clit and you inside her should drive her crazy! Hope this helps! Wrap it up too by the way!!!!
first time usually is painful rather than pleasurable.. by the third and fourth time when both of you are comfortable psychologically and physically she shall feel.. besides the peak level of girls is a bit higher than that of guys.. that is guys can reach an orgasmic state faster than girls though not necessarily... good luck..