Thanks for asking he query,
As you have mentioned you have bridge on the affected side, due to poor oral hygiene
and food lodgement there can been inflammation of the surrounding tissues and abscess formation.
Drainage of abscess in the oral cavity leads to nausea, vomitting, halitosis and stomach infections.
You are also having history of sinus surgery
, I would suggest you to visit to an Oral and Maxillofacial Surgeon and get the clinical evaluation done, take an x-ray of the tooth.
Get the abscess drained by the Dentist
Go for scaling, polishing and curettage at the required site.
Take a course of tab Augmentin 625 mg , tab acecolofenac serratiopeptidase
thrice for 3-5 days .
Use antiseptic mouthwash gargles like chlorhexidine
or betadine gargles twice daily to prevent further infections.
Hope this helps out.