Hi there, thanks for asking. It is very common that the physical symptoms of nicotine withdrawal last until 2 to 3 weeks. You should worry about it. You can ask doctor to give you a medication to treat nausea and vomiting or you can take an over the counter medication to treat it. Vitamin B6 can also manage nausea and vomiting and does not have any side effect. Some people prefer to quit smoking with asking their doctor to give them a medication to treat any symptom and they start to take it seven to ten days before quit smoking.
You can also use nicotine patch during the fist several weeks and it is safe and helps you not vomit. You can use it as another option if it is continued for more than one or two days.
Feel free to ask me any other question in this regard.
I wish you a good health.

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