PLease HElp my girlfriend makes me feel unloved,unwanted what shou

you may not see this as a big deal but I take things to heart, my girlfriend and I have been going out for 3 months were both 16 when she is alone with me we have fun together but if I get sexual in any way, as in just wanting to see her breasts she doesnt trust me . also the other day she would be on top of me and go lower and lower by my crotch area as if she would give me a bj (my penis is 7in not matter of size or anythng) her last boyfriend was like 5in, anyway she just did nothing , then I just let it go it was almost as if she was teasing me , but anyway that same day she went down and did it again and she asked if I would be ok with a blwjb (mind you after 3 months I believe a bj is in order) I sed yes and she licked it a little and then just stopped and sed she wasnt going to, I was pretty annoyed and angered by this and I didnt say that but you could tell by how I was acting I guess, she tried to cheer me up by kissing my cheek and stuff but I was still pretty angry, then she sed your just mad because I didnt do anythng with you , so now im the bad guy , (her x boyfriend she let him finger her, give her oral , and she gave him a bj , she only made him wait a MONTH , I may sound childish im sorry =/) its not a matter of looks either im about an 8 out of 10 and hes like a 6 or 7 , am I wrong to be upset ? I love my girlfriend to the death of me but she is so unwilling and I feel like she doesnt trust me or want me and I feel very unloved please advice =(