Speaking as a person who survives off of almsgiving, I can tell you that you have nothing to worry about. You are a truly generous soul; for only one that is worried if they are giving enough are the ones that do, and many times give till it hurts.
I have run into people that have just bought a couple thousand in products, but when asked to buy a sandwich says they do not have anything, whereas, I have met people who are either homeless like myself, or nearly so who will share the last of what they have.
God is truly in you, so do not worry.
Blessed are those that share what they have for they are the reflections of the Lord.