It's a brown snake - Storeria dekayi. Let me guess - not very big at all, and flattens out its head when its frightened (you may not have witnessed this behavior yet).
Brown snakes & their subspecies are extremely common throughout the US. Their main diet consists of earthworms & slugs. When I lived in TX I kept one & fed it red wigglers & it did fine. Cute little snakes.
K