I walked over to the living room. All of a sudden- again. It's happening again.

My head spun for a moment. My vision faded like a half circle. Ringing played like music in my ears. My heart dropped, skipped a beat, and then started pounding. My head felt heavy and I wanted to sink into the floor. I tripped into the couch, gaining my senses back. My heart was still pounding as the ringing faded. "What is this..?" I thought.

SERIOUSLY WHAT IS THIS