Friend, vomiting, and lethargy can be caused by many different medical conditions. It will be difficult for me to determine the exact underlying cause without a hands-on examination and some testing, I am sorry. But, in a puppy, common causes are dietary indiscretion, intestinal parasites, ingestion of a foreign body, infections, etc. to name a few causes. I am really concern about her gums being pale/white, this is a sign that she could be anemic; or, is very dehydrated or blood is shifting to other organs. Dogs that have pale gums and are lethargic often have a fatal outcome without veterinary care, I am sorry. Unfortunately, we are very limited as to what you can do at home. There is nothing I can recommend for you to try at home that would have a significant therapeutic benefit, I am sorry. Your puppy needs to see a veterinarian tonight for a hands-on examination, x-rays and blood work as an initial screening test. In addition, she will need the supportive care of IV fluids, antiemetics, etc. I would strongly recommend taking her to the nearest ER veterinarian, do not wait. I realize that this answer may not be entirely to your liking, and I regret being the bearer of information that you really don’t want to hear. But it would be unfair to you and unprofessional of me were I to provide you with anything less than truthful and honest information. I hope you understand.
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