****! Ive just let the dog out?

OOPS. This sort of thing can happen. I think he will come back home in a couple hours; If not call your local agency and give them a description etc. You already feel bad so I won't rant about doggy danger. Get one of those automatic closers for your door.

i wouldn't worry about asking people on here for their opinions you should be out looking for your dog no matter what time it is . even if it is quiet there are still other animals (wild) and vehicles he can get very hurt if he is not an outside dog that roams around

Call your local shelters [tell them if he has the id tag, or collar on, put up posters, tell neighbors and search for him NOW. Call his name, bring treats, and try to find him. If you don' he may wander far off, and you won't get him back. I hope you find him.

If you don't find him right away keep searching, no matter what

I would go looking for him- if he is not used to being out then he is more likely to get disoriented and not find his way home. It also depends on the weather conditions if it is cold and he is not used to being out then he could get sick from being cold so definitely go looking for it!

No he won't be okay.. When is it ever okay for a dog to be wandering around at 2am?

that blows best wishes in the search and id rely on that he'd come home when he gets hungry

try squeaking a toy or shaking a box of cookies...very loudly....