I have gone through your query and understood your concerns. In my opinion it must be pelvic inflammatory disease
though mostly it is assymptomatic but in your case both uti and flu are ruled out so I will doubt about this if you are sexually active. But if not then you might be having urinary tract infection
which not get treated well so I suggest you to have blood workout for hb levels and also urine culture. Hope this answers your query. Your tiredness
maybe due to anemia
. Take care.