gum pain (periodonitis?)

I’ve brushed morning / evening always; flossed every couple weeks; I know, i know. I’ve never had dental issues; other than one cavity about a decade ago. I used to go get a cleaning 2x / year when I had insurance, last time 4 years ago.

In the last 4-6 weeks, being suddenly unemployed I slacked off brushing every single night; maybe skipping a day here or there when I fall asleep in the couch, for example.

My inner gum at the rear of one inner side has been bothering me for 3-4 weeks. Teeth feel fine, no issues. My gum has felt irritated and I just assumed it was a cold sore(?), or scratched my gum brushing or eating chips, but it hasn’t gotten any better.

Tooth does NOT hurt. Just the gum feels irritated, more than “slightly”. Reading the archives I see periodontitis or gingivitis as possibilities. As of this morning I’m brushing, rinsing with mouth wash , & flossing in the morning, after each meal, & at night. I read it might be a food particle and bacteria.

I regularly drink 32-64 ozs of water daily. I have allergies, so find myself breathing by the mouth occasionally.

Anyone here have any input?

Worst case scenario, I’ll make a dentist appointment, but want to see any alternatives, as I’ll have to put the dentist appointment on a credit card.

Tks