Is my boyfriend gay or am i just crazy?

My boyfriend and i have been dating for 5 months now. He is 19 and im 17 but see things are totally flip floped. I am like the man in our relationship and he is like the woman. He never wants to do anything sexual with me he seriously has an excuse every time. When we are going to bed he wants me to spoon him. I could seriously be half naked in front of him and i don't even think it would faze him. I really love this kid and i guess im just freaking out because my dad is gay. My mom married him and had me and he turned out to be gay and i really don't wanna make the same mistake i guess. I mean i have never seen him check out a guy or do anything gay but why doesn't he want to do anything with me? once again flip floped im the one who wants sex and he doesn't ugh what is going on or what am i doing wrong? please help me.