sleepless night with mouth pain. OHHHHH...I feel really awful. When I lie down my head aches and my mouth is on fire with pain. It goes away when I sit up for a while so I just can't sleep. I tried anbesol to numb it long enough to fall asleep but it quickly wears off. I'm trying to sleep on my back but the back of my head feels painful, sore and stiff cause I'm not used to it. help anyone?