How can i tell if my roomates gay?

I think my roomate is gay but i am not sure. He says he likes to wear christmas sweaters and he just has this sort of gay vibe to him. He acts very bratty and when he wants something he really pesters. Almost like a little girl. Will say things like "Change it now" It a whiny little girl kind of voice. He also trys to hit on girls all the time but says all the wrong things and something bad will happen with a girl and than he will try to lie and say that he hooked up with the girl. He also tends to follow me around when i am talking to a girl and kind of "s" alot. I think he is a bit confused. I think he is gay inside but kind of forces himself to hit on girls to try to convince himself that hes not gay and cant get over it emotionally. And also hits on girls so he does not look gay. I dont know. Any advice or ysis would be helpful. Thanks! i am a psychology major and trying to figure this out.