hhhmmm...Bella had just gotten to be 3 lbs. when she was spayed at 6 months. She did fine on both, no reactions whatsoever. I debated on whether we should continue with her pain meds on the 2 day and tried to hold off on giving it to her but she seemed a little tender and pained so we gave it to her, after the 4th day, she seemed fine and we discontinued the pain meds. I mean, they are just like us, when I had my appendix removed, I was in pain for like a week (or two!), I needed the pain meds, she would too. Yes, they are small, but the dosage they recommend you give to them should cater to their size. I know you are worried Noebella, I'm sure you can tell whether she's in pain or not, its a mother's instinct!