What Causes Pressure Feeling In The Brain?

For about a week now, when ever I make sudden movements with my eyes, or sometimes even randomly I feel pressure in my brain. It's disturbing and makes it hard to concentrate. When it happens I also hear sounds distorted like, as if I was yawning, but it goes with short bursts. Last night I had the biggest one yet, and I swear I would have fainted if it would have continued for long.