I’m worried my mouth guard will stretch my philtrum out again post lip lift. Is this possible over time or am I worrying too muc

I had braces and I also grind my teeth so I wear a mouth guard (retainer) when I sleep. It’s a rather thick one too and it makes my philtrum stick out. I think after I received this mouth guard, my philtrum stretched quite a bit (after 3 years of nightly use) and so I received a lip lift. Now I’m worried my mouth guard will stretch it out again. Is this possible over time or am I worrying too much?