Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain it seems that sores in mouth along with fever and chills and also having a history of intimate contact with a women having multiple partners..
Well, it can be due to causes other than canker
sores and one of the most common cause for it can be herpes
virus infection causing cold sores..
It generally occurs with intimate contact with an infected individual and as you have a partner who further has multiple partner, therefore it can be most probable cause as canker sores generally does not cause fever and chills but herpes can..
I would suggest you to consult an Infectious Medicine specialist and get evaluated and a thorough clinical evaluation and investigations like oral swab culture, IgG and IgM antibodies
for HSV 1 can help in diagnosis and treatment can be done accordingly..
In case if it is herpes oral and topical antiviral
medications like Acyclovir
, Valacyclovir etc can be advised for reducing and frequency of the outbreaks..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.