The noise was probably the deer "blowing" or "snorting". They do this to clear their nose to get a better scent of you and also to alert any others to your presence. Really, you should not even be considering a shot before legal hours. What if the "deer" in the dark turns out to be someones horse or even another hunter? Many people are certain they see some game and find out after the shot that they have just ended someone's life and ruined their own. Playing paintball, even for a lifetime, does not qualify one to hunt. Not even close, Sport. You don't have to be an expert on deer behavior to begin hunting. Many people learn as they go and that is fine. You SHOULD be an expert in the safe practicesof handling a lethal weapon and have some foundation for good decision making in the moment of truth. That is where a mentor would really come in handy. I do wish you good luck and hope you keep on hunting in the future. Just remember that the second after a bullet or arrow is released, it can never be taken back. Please follow all laws and postively identify your target.