If you have finished Invisalign, did your teeth “settle” afterwards?

I have one more aligner to go to finish my refinements and this should be the end of my treatment. My teeth are lovely and straight now but when I bite together they don’t feel particularly natural in the way the upper and lower teeth touch. My dentist told me that once I’m in retainers, my teeth will “settle” and close together more tightly. Does this actually happen or should I consider asking my orthodontist for another set of refinements?