Is it normal if i don't know if i like a guy?

There is this guy who I have been friends with forever. Over the past year we have started to do things that are a little more then friendy. last summer on his birthday we were playing truth or dare. I got dared to give him a hand job, and I did. And one night we were in the back seat of a car together and he put his hand on my thigh and kept moving upward. I did the same, and this went on for the entire ride.

The problem is that I don't know if I really like the guy or not. I think I might because any time I see another girl flirting with him, I get really, really mad, but I don't feel the same way I do with other guys I like, when I'm talking to him.

What should I do???