Over the weekend I experienced a burning sensation from the base of my neck up to my lower jaw (as if someone was yanking the muscle between). Then came the burning sensation at the top of my head and all of this was on the left side. I took some painkillers and it went away. But this morning, I woke up with excrutiating pain in the same areas. However, this time I tasted blood in my mouth (which there was none). Also some dizziness and since then, my eyes and base of head have been burning. The pain in my neck and jaw is not as bad, but a dull thud and my mouth has a metal taste. What could be the cause of this?