Metacam

My vet prescibed metacam for my cat after extracting some teeth. Before
surgery the vet did a blood test, which was normal. A few days after
surgery, she stopped eating..snobbing her favorite foods. I didn't think
much of it because if I had teeth extracted, I'd wouldnt have any interest
in eating either. A week has pasted by and I noticed she is drinking water
more frequently and started walking like she was disoriented & some
vomiting occured. I was concerned and called the vet. He did some testing
and now he indicated that my cat has some kidney damage. I asked him how
can that be when you checked her blood? He can't understand why. My cat
also had mouth ulcer and stomach acid of some sort. Now, he gave me iv for
her dehydration and antibiotic plus something for her stomach acids. The
dosage her prescribe were .6ml the first day then .3ml once a day for four
days, then .1ml three times a week. He didn't warn me of any side effects.
Can the Metacam be the cause of some damage to my poor kittys kidney?
Very concerned. Just an fyi-I paid $425 for the dental/anesth+iv/extraction
of teeth. Now w/the complications they charged me $ 268.