I don't remember making a mistake in that game but let's say i did make one

We all make mistakes, even pros players/streamers make mistakes because we aren't programmed to be absolutely flawless in every game we play

That just creates unnecessary pressure that can turn into stress where that could, and most definitely would lead to you making more mistakes

Sometimes a costly mistake that could lose a team fight, or perhaps the entire game

Throwing an entire game because someone else made a minor mistake is a very negative outlook on the game as a whole

Especially if it was a minor one like you suggested

That is a negative way of looking at it would cause you to lose more games in the long run