How long do hangovers last usually?

Gf had a lot of shots last night and has been puking since (currently now 7:30pm, so it’s been about 24 hrs). She’s got no appetite, can’t stomach even seeing or thinking of food. She can hold water down now as of a few hours ago. Puked a lot before bed and this morning. Last time she puked was about 3-4 hrs ago. Constant nausea not in waves, no headache.

Gave her 2 Dramamine around 11am, then another two around 4pm, hasn’t helped at all.

Any suggestions would be fantastic because idk what else to do or give her and I feel awful because she’s feeling so shitty rn

Edit: she actually just puked again