I'm 27 f. i've thrown up a lot now and now i have a hollow feeling in my chest what should i do?

Get help: Your ongoing vomiting must be treated. You can end up with dehydration, loss of nutrition, and salt (electrolyte) imbalances that can become life-threatening. Your vomiting itself is more threatening than the chest sensation. See a clinician as soon as you can. Hope that helps.

Go to ER: You might be getting dehydrated. Its very hard to replenish the water in your body fro a lot of throwing, so best way is go to ER. they can give you IV fluids and make you comfortable.