Hey π
It's very hard to answer without being able to see the plant or the mite itself well. So unfortunately, I can't give a general answer.
You can have several types of mites. There are good mites for your plant, and there are bad mites for your plant.
Among the bad ones are spider mites. You can recognize them because they initially gather a lot on the underside of your leaves and later wrap their spider-like threads around the leaves and the area. Neem oil helps against this.
However, not all are bad. In general, you could say: if the mites are quick when you try to touch them, they are very likely to be small predatory mites... these are great for your plants because they keep harmful ones like the above away from your plant!
It's best to just look at the plant to see if you discover any damage. At the same time, check where the mites are gathering and how quickly they move.
Hope that helps!
Good luck, and hopefully the right kind of mites for your grow πππ