It will make you feel good.
Acts of kindness are oftentimes more for the person doing the act than the recipient.
Doing good deeds is related to a whole host of health benefits, including weight control, blood pressure, chronic pain, and depression. The brain releases "feel-good" neurotransmitters when you give charitably, in a cycle that phsycologists call "the helper's high" .
It may make you feel good to give in the moment, but if you are conflicted about whether it was the right decision you may ultimately feel worse.
Giving to beggars is not a good deed and as such will not make you feel good.