Normally I get my indoor plants from Ls but a few weeks ago I was at HD and grabbed a tiny plant there. When I got home I repotted it and added it to my collection in my room, but several days later I noticed on the underside of one of the leaves a tiny red dot that moved. I deconed the plant in the most paranoid of fashions (alcohol, water, soapy water, water, neem oil, then neem oil every day for the next 3 days + pesticide) and left it outside away from my indoor plants but I was always worried a mite might have crawled its way to my other plants. Well, today I noticed a red moving dot on the leaf of the plant that was right next to the one I dumped outside. I squished it with my nail and it left a red streak. I paranoid deconed that plant too in the shower and it seems to be clean (insecticide, soapy water, rinsed, insecticide but only on the dirt and parts connected to the dirt) What I want to know is, where are these mites coming from and should I be worried there might be more on my plants that I just can't see?

Extra info: On both sightings, I had investigated the entire plant before washing it and only found 1 single red mite. On the recently bought plant, it had some minor webbings on a few of the undersides of leaves with white and black stuff in the webbings even though I had rinsed the plant with water before taking it inside. On the plant today, it was all clean except for one string that looked like a travel string and the mite wasn't on that leaf. I used a magnifying glass to check for anything else but I didn't notice anything 'off'. I also gave a quick check to my other plants and haven't found anything. Also, I noticed the mites on the leaves closest to me, but I still had to lift that leaf up.

I'm probably being an over worried parent but I've never had my indoor plants be infected with anything before, and I've never dealt with these tiny red mites/bugs before either, even outside, so any information is appreciated.

Also, when I work or relax outside, I usually go to my room and sit at my pc afterwards (the room where my plants are in). If i'm bringing these red things in on me, is there a way to get them off before coming in?