Have I suffered a concussion? A week ago, I passed out and hit the back of my head on the ground while I was abroad. I thought I had recovered after a few hours, but the plane ride home left me feeling very weak and nauseous. These past few days, I have experienced a lot of dizziness and nausea. These feelings intensify after I eat. I feel unbalanced when I walk, and woke up this morning with ringing in my left ear that disappeared after 10 minutes. Should I be concerned? I am also scheduled to undergo liposuction/fat transfer in a week. Am I still OK to undergo the procedure?