So one of my molars right now is decaying. Last year around August I noticed there was a chip there but I just ignored it and figured it was just a chip in my tooth and around December I noticed it got way way bigger than it used to so I was suddenly getting worried. Last february I finally found the time and the budget to get my teeth cleaned and that chip now hole checked. The dentist there said that I had to have it removed or get a root canal. The problem is I'm wearing retainers and my retainers kind of clips onto that molar. I was worried that I would either have to get a fake tooth or have to wear braces again or something since i'm scared of my teeth moving back again. I was supposed to go to my orthodontist last march but because of the recent coronavirus pandemic and my country being on lockdown I wasn't able to deal with it and have it fixed. Now it's starting to hurt and i'm even more worried now because it never hurt then. I looked at it using a mirror and it wasn't pleasant to look at. I was just wondering what can I do to ease the pain and maybe possibly slow down the decay of my tooth just until things get back to somehow some type of normal.

TL;DR took too long to deal with my decaying tooth now i'm stuck in quarantine and my tooth is starting to hurt, what can i do to ease the pain and slow down the decay just until i can finally get it checked

Thanks!