Is it normal to be confused about your sexuality?

I'm 18 and I'm a guy. I've never been in a relationship before and only have 1 close friend, who is also a guy.

I've never had sex with a girl before. I think I would enjoy sex with a girl, but I've never tried it.

There's been a few dozen times that I messed around, but they were with guys. It was fun, but I didn't really feel attracted to them at all, I just liked the sex. They were all people I used to be friends with who were curious like I was.

I do enjoy sex with guys, and there's been times where I've seen a guy and thought "he's hot". But I've felt the same way about girls before too. I really can't see myself in a long term relationship with a guy, though. I also don't feel emotionally attracted to guys (well, there was one guy but he's like a brother to me, and I don't feel anything sexual towards him. All the things that would be "gay" in guy friendships really don't bother me when I'm with him. They still bother him though, so I get lots of jokes out of it, although it does make our friendship extremely confusing sometimes. I could see myself having sex with him, but I really couldn't see us being in a relationship. He's pretty hot, so it's not like I've never had that tingle in my pants when I'm around him).

My porn watching habits are kind of strange too. I've watched lesbian porn but it didn't really interest me. Regular porn is exciting, but my favorite has always been gay porn and I don't really know why.

I think I'm straight but I'm so confused.