It's also possible that what you're feeling is from parasites of some sort in your liver...that may sound far-fetched, but 6 months ago, I would have told you you were crazy if you'd said I had parasites but since then, I've seen the proof! In my case, the primary critter is the liver fluke and I've been known to feel fluttering in my liver, which I believe is due to the flukes.
Damage from drinking/partying, in my opinion, wouldn't necessarily display as a feeling of movement in your liver...I could be wrong, but I think it's more likely to feel like a dull ache or a sensation of fullness if your liver is sluggish.
In either case, a series of cleanses is what I'd recommend, but you don't want to just start with a Liver Flush
-- you need to do some preliminary things so your body's prepared for that. Do a bowel/colon cleanse first along with a parasite cleanse. You'll probably need to do the parasite cleanse for close to a month before you're ready to do a liver flush.