hello and welcome to HCM forum,
first of all stay calm, the infection in your tooth has not spread anywhere else in your body so don't worry, your dentist
made an opening in your tooth so that all the pus and the infection seeps out, to give you relief from pain.
also, you have been taking painkillers quite often , nausea
are the side effects of medication. do not overdose yourself with painkillers.
kindly trust your dentist and continue with doctor prescribed medication only,
i would recommend a few measure for you to follow;
1. warm saline rinses,
) mouth rinse(3-4 times/day),
3. visit your dentist whenever required.
i wish you good health,