It's ok to make mistakes, people are generally understanding and it's usually not as bad as you think. The main thing is that you replay the mistake over and over in your mind constantly for several weeks after it happens. Once that's done you can just add it to the backlog of embarrassments that your brain can randomly select from during otherwise peaceful moments.
if you (not you specifically but anyone reading) find this happens often enough to be debilitating you may benefit from seeing a psychiatrist for anxiety/depression medication. My wife was like that and it made an immediate difference for her.