I forgot to throw out last weeks Invisalign tray(s) I put this weeks tray(s)in the same spot. How do I know if I'm wearing the right tray? I'm not sure which tray is my current tray. I tried each top tray and bottom tray to see which one felt tighter. But, I'm unsure if what I need to be looking for is tightness or something else to make sure I'm wearing the right tray(s).