This is Dr Basu, experienced Internal Medicine Specialist.
I am here to address your concerns and provide great service.
This can be a skin infection appearing as skin pimple.
May be related to the ruptured polyp or cyst --spread of infection.
However you are not having any fever which is reassuring suggesting at least not serious infection.
You can try over the counter Bacitracin ointment over the pimple.
But do see your doctor by tomorrow or go to urgent care for oral antibiotic course for proper treatment of infection.
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