Do you suffer from impostor syndrome when it comes to your GMing?
Are you aware what it is?
For those that don't know, Impostor Syndrome is when your brain tries to convince you that you're a fraud at whatever it is you are doing, and that it is only a matter of time before everyone figures out that you've been fooling them this entire time. It frequently happens for people regarding either their talents when it comes to creation (artists of all types talk about it a lot), and can also happen with regards to someone's job especially after they get a promotion.
In short, it is insecurity fucking with you.
The thing is, I've seen people who GM games have it too. Hell, I have had it. I have it semi-regularly. It makes sense. GMing is a creative endeavor. Your players are looking to you for a fun time. It is easy to convince yourself that you're a horrible GM, that you're a fraud, the game is only fun because of the players and that any moment they're going to realize that and then...who knows, cut you out? Stop playing? Have someone better take over?
The thing about Impostor Syndrome is it can also put a lot of undue pressure on you. You feel compelled to do more prep, to try harder, to reach for more than maybe you're currently able to handle with your sessions. You hold yourself to unreasonable standards. Comparing yourself to GMs like Matt Mercer when it comes to portraying NPCs even though you're not a professional voice actor with years of experience and education in acting and portraying characters. Or to other GMs who also have their own games, own players, own styles, and own games.
To be blunt, Impostor Syndrome sucks. However, it can be fought.
The first thing is to recognize it for what it is.
The second is to apply logic. People would not be part of your game if they weren't having fun. If you ask your players if they're having a good time, and they consistently say yes you can believe them. If people are looking forward to game, regularly attending, and showing up on time/staying for the whole session without 'other plans' regularly getting in the way? Those are all strong indicators they're enjoying the game.
You don't need to be a Matt Mercer, Matt Colville, Brandon Dixon, Chris Perkins, Shareef Jackson, or Satine Phoenix. You just need to be you. You have your strengths and weaknesses, just like they have theirs. So be the best you, and run your game.
You got this.