What the heck was that about? lol?

I was talking to a good guy friend about something stupid he did so I had a slightly sour face but didn't notice. My girlfriend came up and said my face looked weird, and I was like "what? that's not nice" and mildly pouted. Then the guy came over and poked both my checks with his index fingers so that my lips squished out in a fishy face lol. What the heck? lol Is he weird or flirting or what?