confused....

Today 2 of my friends told me that one of my best friends is flirting with me. He has a g/f who is another one of my best friends but she is going to a different school. He has poked me and played with my hair. He has done alot of strange things but i'm not sure if he was flirting. If he is flirting i would be kind of creeped out. I'm scared that if he is flirting my friend (his g/f) will find out and never want to speak with me again. I don't think of him as more then a best friend and would never want to hurt her (his g/f). What can i do before this gets way out of hand?

just don't respond in anyway you'll be safe if you don't respond your friend (his g/f) would be mentally retarded if she got mad at you if you didn't respond