Reminds me of a bit from a comedian I once saw on Russel Howard Hour (Troy Hawke), and I'm paraphrasing a bit here:
"You know who doesn't have Imposter Syndrome? Imposters. Go pretend you work at B&Q for a day and see what it's like to be an imposter. You can get angry about anything and it won't mean shit tomorrow. So when you feel like you have Imposter Syndrome, remember what it's like when you, eventually, get kicked out by security. Remember you are physically, emotionally and intellectually capable of your REAL job because you self-analyse and self-reflect. And because you self-analyse and self-reflect and self-doubt means you're good at your job. You give so much of a shit about what you do that you're worrying about not doing a good job."
Makes the pain of Imposter Syndrome a bit easier to bear knowing it's because I give a shit and, hopefully, that means I'm doing a good job.