Opalescence whitening - as of right now, I'm not impressed

I traditionally haven't had luck with whitening trays in the last so I decided to do in office whitening with opalescence. I used sensodyne for 2 wks before and took ibuprofen an hour before. I did (2) twenty min sessions. When we were done, I didnt see any change! I did have a white spot on my gum where the peroxide got on it and caused a burn, but other than that I didn't have pain. The next day is when my teeth felt sensitive. I'm going to follow with the take home trays for 2 weeks to a month (depending on results). I'll update after that. As of right now, I'm not impressed.