rating going up and down

Hello everyone
I've been playing on lichess for a few years and my rating ranges from 1600 to 1700.
I mostly play 3 minutes games.
Some days I log in and within an hour or two I go from 1600 to 1700, and the next day I quickly drop back from 1700 to 1600.

I wonder if lichess has a way to "fix" my games, meaning to match me with opponents that I have a high probability of beating (of course the ratings of all my opponents is always within 50 points more or less than mine)

Am i paranoid?