Message on the windshield

To preface the short story I am about to tell you, you must know a few things:

1) My boss is building a shop next door to the daycare.

2) There have been construction workers (all older men) there for the last few weeks, but never were there any younger ones.

Yesterday I got off work and walked out to my car. As I was pulling away I passed a truck with two guys in it. I only say one of their faces and he was handsome! And younger than any of the other guys. He waved at me and I waved back and smiled. I texted my friend at the stop sign and was like, "There is a really cute guy working out there today" - she, being the great friend that she is asked if I wanted her to go get his phone number for me. haha. I told her most definitely not! He is probably married and was just being friendly.

Well, this morning their truck was there, but no guys. I really thought nothing of it, because I really did think this guy was married. BUT when I left this afternoon I realized there was a piece of paper folded up and stuck under my windshield wiper. I AM NOT EVEN KIDDING! So I stop my car and get it and open it up.

"Hi!
I'm the guy who waved at you yesterday at the daycare parking lot.
If you are single, call me. I would like to take ya out sometime.
Phone #, Paul"

I called my friend and was like, "This isn't funny!" But she didn't write it, and she didn't talk to him yesterday.

So now, I'm not really sure what to do. Do I let it fizzle out and not do anything? Do I call him tomorrow? Do I try and leave a note on their truck with my phone number so he has to call me?