Does he think I'm pretty ?

Why are you asking yahoo? Go ask him yourself. Tell him you need to feel more secure in this relationship and that in the two years you've been together, he's never really called you his girlfriend. Say you want it to be, for lack of better word, more official. Plus, no matter how you look, he should be treating you like royalty on high -- if you're beautiful, he should tell you that, cute and pretty shouldn't cut it at this point.