AITA for not letting this guy use my phone.

I was hanging out at the bus station when this young, sorta unhealthy looking asian guy walks up to me pushing his bike along and says ," I do kung fu on you if you don't give me phone now!" . His question was a bit direct and didn't feel very polite in tone. I declined because I don't know if hes going to snatch it and run off happens often here. He walked away angrily saying something like, "when the diarreah flow in toilet bowl it become the toilet bowl, flow like diarreah my friend" or something but its funny cause I'm not even poop. The more I think about it though the more the situation rubs me the wrong way. I'm too terribly kind and I hate making me people angry. What if it was an emergency? I dunno I'm sure he would have said something. What do you think?