[OMFG!You'reActuallySmart!]

I doubt you'd ruin your liver when doing this once but since you said you've done it multiple times, you could be causing progressively more and more damage to your body. If you think your liver is screwed up, then look in the mirror at your eyes and skin to see if they're jaundiced. If so, and if they weren't before, then you've got yourself into a monstrosity of a mess. If not, then I would say to still head to the hospital to get you assessed.