HI.
Thanks for your query and an elucidate history.
The cause of pain in testicle:::
-
Epididymo-orchitis, since your partner has yellow
vaginal discharge, you getting UTI and retro-grade infection is a great possibility.
-Torsion, if inadequate and recurrent can cause the similar pains reducing and increasing as you described.
-Varicocele can cause local and
abdominal pain.
I would advise you the following:
Urine -routine, microscopy, culture and sensitivity before start of the antibiotic.
Blood
Ultrasonography and color doppler examination of the abdomen for genito-
urinary system and scrotum
Gynecologist's examination of your partner and ful course of antibiotic, metronidazole, anti-fungal for both of you.
No sex till your both are cured.
to use condom later on.