Wisdom tooth removal & dc gave me amoxicillin & metronidazole.i got back pain in left side & dark yellow urine.is it kidney stone or medicine effect?

Probably med effect: Metronidazole is known to turn urine a brownish color. Also, being dehydrated can also make your urine look dark. Kidney stones usually cause pain and may be associated with blood in the urine.

Kidney stone : Most likely kidney stone as the symptoms you're describing are not consistent with 3rd molar postoperative sequellae. See your md as the Amoxicillin / Flagyl is xlnt coverage for the extraction. Hope this helps... Good luck.