I feel like something is drilling my forehead. heavy pressure inside my head, mostly on the back of the head. sometimes i feel like water falling inside my head & a cool breeze flowing inside. what medical condition is this? what are ways to fix it?

There are a variety of nerves running along the head/face. Any drilling, watery, cold, tingling, or burning sensation could be the result of improper stimulation of these nerves = parasthesia. If this is a recurring sensation or you have strange sensations in multiple areas, and pain in your head, it might be time to see a neurologist. They can do nerve testing and determine the underlying cause