This might sound asinine if you have already done it, but in the event that you haven't...plug it in to THE WALL via the apple cable/brick overnight, at least 8 hours.

This works quite often if it's a result of being dead for a while. So while you may have had another problem that's sorted itself out, it won't "revive" until this is done. I've had more than a few neglected electronics that just needed some love from the wall.

Also...if you got it wet, I've read putting any phone, into a bowl/bucket whatever, surround it with dry rice, that the rice absorbs the moisture. I've never needed it, but I've heard of lots of people getting success from this.