WWJD?

So I'm sure you all know the above initialism, right? Well there's a new one - it's WWPD (What Would Patrick Do? - and then do the complete opposite)!
I really showed my true colours there yesterday and I'm not feeling very happy about it. In Dublin, it is not uncommon to see people begging on the streets. With the expansion of continental-style terrace dining, it's also not uncommon to have people come up and ask you for money when you're sitting outside a pub or restaurant.
Now I never take out my wallet on the streets. It's something I'm not at all comfortable with. Most of my friends are different and give as often as they can. So I was sitting outside a pub in the centre of Dublin with some friends yesterday, soaking up some very rare rays of sun, and this guy comes along and slurs, "Now you can tell me if I'm disturbing you and I'll move on but do you have any spare change?" Before any of my friends had a chance to answer, and without even thinking about it too much, I answered, "If you wouldn't mind..." To give him his due, he did move on to the next table and just shouted back, "It's just that I'm f___ing hungry!"
My friends didn't call me on this at all, but I know that if I had said nothing they would have given him some money.
I'm still trying to process what I did from a philosophical point of view. If I had given him money, it wouldn't have been because I wanted to help him out - it would just have been because I wanted him to go away. And then, I could have lied and said I had no change - which is what all the other people on the terrace did, but I actually wanted to let him know that I didn't agree with what he was doing.
I do believe in charity, and I give in other ways - but I'm fiercely protective of my private space. However, the incident, because it was all done without much thinking, has really shown me that I'm not a very good person. I think karma-wise I'm looking at some serious universal retribution. I don't know - not a good experience.