Is this traits of a stalker? What should I do?

A very weird man asked me for my number, after I told him yes i have a boyfriend, im 19 the stranger is 24 , I'm not sure where he lives but he was in my neighborhood area so I told him maybe later, hoping to not see that weirdo. A week later he catches me again and says hey, I've been looking for you, I like you, what have you been doing blah blah blah. Can I have your number, I say thats weird that youve been looking for me, and I say maybe I don't know and go inside. He stays outside with some workers who are fixing a pipe, and he smokes a cigar and watche them, and I never return to give him my phone number. I'm not interested in talking to him or anything, total loser I've only seen him twice.