Hello there ,
Thanks for writing your query,
According to your clinical history i suspect you have developed a gingival abscess
or a gum boil that is draining white pus in the oral cavity with fowl mouth odor.
It is caused due poor oral hygiene
,improper brushing and flossing that leads to accumulation of bacterial plaque
and calculus deep in the gum pockets and root surfaces of the teeth.
It needs to be treated by thorough professional deep scaling of gums and root planing of the teeth to remove all the irritants ,this will help in resolving the symptoms .
followed by a course of antibiotic and analgesics.
i would suggest you to go for symptomatic treatment at home like gargling with lukewarm saline water or antiseptic mouthwash like chlorhexidine
i hope this helps ,