Should I be flattered? Or what?

The other day I went to the post office to drop of some mail.
I was pulling out of the street at the stop sign to get into Livingston Ave. when this Old man made a turn to get in the post office drive way. And he just stopped there and smiled at me. So I smiled back. Then he said this are his word and I quote:
Old man: you are a very beautiful young lady
Moi: Uhh, thank you
Old man: yes, you are very pretty
Moi: uhh, thank you
Old man: Nice to meet you
Moi: "grinning" nice to meet you too. (Mind you, that I am really holding my laughter)
Old man: So do you want a Sugar Daddy?
Moi: Uhh (have a confused face) what?
Old man: Can I be your Sugar Daddy?
Moi: NO thanks,
Old man: Are u sure? I will take care of you.
Moi: No, I can take care of myself thank you very much.
Old man: um um um (shaking his head, and smiling) then he drove off.
I just sat there in my car and said to my self: wow, what in the world was that?
Seriously I was trying to make sure that I wasn’t dreaming. I mean this guy looked like he was in his fifties or sixties. I was thinking this is someone’s Grad-Pa.
No I wasn’t dreaming, it actually had just happened. I really don’t know if I should be flattered or be sickened by it. Really? I mean how crazy was that?
I still don’t know how I feel about it. Most definitely a weird experience.
If this had happened couple years ago I know would have been mad at the guy. I would have called him names of something. I don’t think I did anything for him to say that to me? Or did I? I don’t know, I am confused. But leaving the sick part aside it’s kind of embarrassing and funny. Isn’t it?

For those who don’t know what “Sugar Daddy” means
sugar daddy: a wealthy older man who gives a young person expensive gifts in return for friendship or itimacy.

On second thoughts after reading this I am actually fuming. We can call it delayed reaction.

Gosh what did I do to deserve this?