HiWelcome to Just AnswerSorry to hear about your problem.
Well, if the infections have been reliably ruled out by tests; then the other causes for this symptom including the ones you have mentioned can be considered.
Minor trauma to urethra during intercourse.
A stone in the urinary tract that may cause a radiating pain.
Stone in urethra.
If not already done, also get an Ultrasound of the renal tract to look for stones in the urinary tract and always Drink plenty of water.
I hope this clarifies and answers your question.
Kindest Regards and Good luck.
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