A little missunderstanding

I went to the shop today to buy some food. We had nothing at home. On the way back a man came up to me and really I thought he you know came on to me. That is what they usally do when they smile and say Hi. It was the way he started the conversation.  well this is how the conversation went:

The man (TM): Hi
Me: eh, hi... I was thinking, what the h*** does he want?
TM: May I speak with you?
Me: Why would you want to do that?  Yeah I admit it, I did have some aditude, but he really made me irritated.
Now the man looked a bit embarrassed and was like saying eh, eh. I looked at him clearly irritated
Me: Hey, I am married and I have children so..... Now I am starting to go away from him.
TM: Oh, no that is not what I ment. I just wanted to know where you can put up notes if you want to rent a room in this neighbourhood?
Me: Oh I am sorry but I don´t know that.
TM: hey, don´t think like that.
Me: I´m sorry. But I wasn´t really. He had it coming. That is what I think at least.

OK so I mean really if you just want to ask a starnger something you really don´t start the conversation like that. I mean I wouldn´t do that, I would say something like: excuse me, may I ask.......? Right? isn´t that more normal?