Extreme pain after not wearing trays for 3 weeks. Should I just push through?

My doctor told me to keep the tray I am in for a month. I didn’t wear this tray for a little over 3 weeks. My appointment is in a week so I put my trays back in. I am suffering from a lot of pain. I tried to go some trays back, but my teeth fit these the bests I am experiencing nausea and headaches. I would like to push through and hope these fit before my appointment. I didn’t think 3 weeks would make a difference but the pain seems dangerous. Should I just push through? Should I be worried?