You may say creationism is only a doctrine or a way of faith. Then how do you describe your "big bang?" Were you there to see it? Do you have any proof that the chemicals where there? Has anyone who was there to see it told you about it?
If you're honest, the answer to all of those questions is no. And then, doesn't that make you a preacher spewing out strings of doctrine hoping to tangle down someone with faith in creation?
No one alive today was there to see what happened. Both ways require faith. Both ways require you to believe in something that was here before you. I take much more comfort in believing in a caring creator than some cosmic chemicals.