Thank you for your question.
of 13 days, investigations will need to be done. Particularly urine analysis, ultrasound
of abdomen and pelvis and further tests if needed. A physician can perform a clinical examination to determine if the cause is in your back vertebrae or it is myalgia
associated with systemic disease. Possibility of urinary tract infection
is high if there are any associated urinary symptoms. The cause of fever and how long will it last can only be decided on examination and above mentioned tests.
Hope this is helpful.