I wouldn't even think of calling you a sucker. You might just be right, you were put there to help her. And maybe also you were given the chance to share. I do believe in Angels and incidents that are not quite ordinary like this one, do test us sometimes.
Bless you and thanks for sharing your random act of kindness, it could inspire someone else to do the same. I remember a story on this site around last Christmas of a woman that gave a favorite coat to someone that needed it. There really is kindness in this world, we just need more of it.