Looks like a flake of flint.I do see some posible edge work on the right side near the tip,so it could possibly be a flake knife,but its not an arrowhead.
Hi... thought I'd clarify these replies just in case you're not familiar with the jargon yet. The jargon can be enough to scare a person away from the hobby.
"Preform" is a crudely worked chunk of stone that someone intends to use to make a stone tool. "Geofact" is just a natural stone that has not been modified by people. A flake knife is a basic ancient tool made by breaking off sharp pieces of flint.