I had 8 teeth pulled at once, many years ago. I couldn't take Tylenol 3s as they made me sick. I did my best with ibuprofen and acetaminophen (one Motrin, one Tylenol extra strength). My father kept me distracted as much as possible. His advice was to keep your mind distracted as it can help with the pain.
It depends on the situation.
In my previous job, all of my coworkers knew. Management had no clue. They were all supportive and helped be a reference.
In another previous job (long before my last one), I would apply to jobs after work hours and "book" doctors/dentist/car mechanic appointments to do the interviews.
I never ran into gossips, so I've no advice for that.
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