Does it make sense to pay for yet another office visit to a vet when they’ve already diagnosed my cat?

I took my cat to an Emergency vet the other night and they diagnosed her w/ some kind of arthritis and/or joint pain. Her only symptom was lack of energy and low mobility. All blood work came back normal. They gave her a 1mg dose of metacam and sent me home to give her .5mg for the next 2 days and then .1mg twice a week. The next morning after the 1mg dose, she was doing great. But now she has deteriorated again, even with the .5 doses. The original vet who saw her was not in the office today and the technician says they can’t do anything else without us coming back in. Why should I pay another $85 on top of the $300 I already paid when she was already diagnosed (correctly, in my opinion) and the initial treatment worked. Why can’t they just adjust the dosage or prescribe another anti-inflammatory? The vet who saw her will be in tomorrow and I’m hoping she will take care of it over the phone. Am I just being a bad kitty mother? Non-serious answers will be reported as abuse