Am I stupid? Or what?

Here's the story goes.

I took bus 24 to work at Expo. I alighted at the bustop. Intended to J-walk the road.
Was called by a uncle sitting on one of the seat on the bus-stop. He ask me to help him see if there is any bus to NTU a hospital. I am thinking got Hospital called NTU meh, that's not a uni meh?! Never mind maybe this chinese uncle remember wrongly, no point urge with him. So i help him see the board. Saw only one bus going to General hospital. He told me that he met another person earlier that ask him to take bus 9 from the bus-stop that is quite far, on the other side. He show me his left leg, broken so he have to walk in stick. I pity him, so i ask him, can u walk there?
The uncle say he needs someone to help him walk to the bus-stop or he have to take a taxi. I am almost late for work so i ask him how much do he need? I dunnoe how it ended up i giving him $22 for the taxi. He says he will return it to me and claims that he has no intention to cheat me. And the funny part is he keeps trying to push me into taking his newspaper, saying i can read the paper.

After quite some time, i realised that i am stupid. The money lost is not the main issue. The important part is there are people out there cheating money out of people who are kind, or perhaps, a better word would be naive. Ya. This is how kind person always dies earlier then bad people. They trust the wrong person.