I suddenly had an episode of an enormous amount of pressure in my head and my hearing goes muffled. It has happened a few times before, but this time was scary. I started seeing black from the sides like I was about to faint. The episode only lasts for a minute or two, not very long. I went to the ER, had a spinal tap, CT scan and an EKG all with normal results. I will follow up with my regular doctor, but I am so worried and need some guidance now as I have severe anxiety.