Maybe you're not an Atheist, maybe you're a Naturalist.

Atheism is a reaction against theism. It is purely a rejection of an idea. It's not a positive substantive idea about how the world is. Naturalism is a counterpart to theism. Theism says there’s the physical world and god. Naturalism says there’s only the natural world (with or without scientific proof, ie. through logical and mathematical deduction)

I don't enough FAITH to be an ATHEIST.