Just started on Mobic and having issues...

I dislocated/tore/fractured my knee 10 months ago. My new orthopedic surgeon put me on Mobic as a first step in care. I was scheduled for surgery before we got orders to move. I started on Mobic 5 days ago...and my issue with it is it's making my knee hurt more. I'll take my pill in the morning and within an hour my pain level goes from 3-4 (my normal daily pain level) to around 6-7 for around 5-6 hours until it goes back down to my average 3-4. My sister (an RN) and an ortho friend back home both say to give it at least a week before i call the doctor up and tell him whats going on. he wanted me to stick with this for a month before I go back in and possibly start injections. I guess I'm wondering if this is normal? I doubt it is. I feel like my Dr just put me on it to shut me up because he's clearly convinced nothing is wrong with me. Anyone have prior mobic experience?