Haven't worn Invisalign for awhile; tray doesn't fit great, can I keep on this path of Invisalign or is all hope lost? (Photo)

Visit your local dentist to discuss options for a "few" additional aligners.  It would be the best way to get your teeth back to alignment and be sure to discuss proper retainers to keep your teeth aligned and straight FOREVER!Good luck!

I would recommend just trying on the tray 1 or two trays back to see if you your teeth feel better.  If they feel better, then I would gradually work back up to my current trays over the next month.  However, if you want to wear your current trays and suffer through the pain, that's an option too because I would expect the spaces to close up over time.  Missing Invisalign for 20 days is not a huge deal, it just delays your future end date and may hurt your final results if done repeatedly.  I hope this helps.  Follow me on RealSelf if you have more questions or comments.  

You will need to go back as many trays as necessary until you get to the one that fits and then start over from there.