Am I considered a cheater for doing this? I'm scared that I might be false positive on cheating when I literally didn't, and I swear, I did make a mistake somewhere or could've made a better move too right?
These games can happen, especially when you play against a lower rated player. I've heard lichess has special ways to take care of cheaters, and false positives should not be the case here (I guess that if they were, many GM accounts would be closed already).
But I'm just a chess player and a bad one: my statements might be wrong.
he made blunder If he strong player maybe you lose
congarts!
Very nicely done you played well that game.
On the other hand, your opponent's rating, and play were not so great. It was a short game only 27 moves, everything upto move 8 or so is well known theory, and your opponent blundered very badly dropping queen and rook.
Maybe you need tougher opponents?
Your move times don't suggest cheating, you should be fine.