Overall, it sound like you did pretty good. You just didn't do what you wanted to.
The take home point is it is a learning experience.
There are three referees that essentially vote independently, via red or white lights.
Either two or three of the referees found you violated one of the rules. So, it was NOT a bad call.
Rather than blaming other for your mistake, take responsibility. Find out what you did wrong and correct it.
To paraphrase Tom Hanks in the movie, "A League of Their Own"...
There is NO Crying in Powerlifting!
Fix it and move on.
Psyching yourself out was self induced; you created your own problem. Everyone initially experiences it. Don't blame other for you inability remain calm under pressure.
This take us back learning. You need to learn how to shrug it off and deal with it, as other do.
1) You did well. Focus on that rather than beating yourself up and focusing on the negatives.
2) Don't panic; all it does is make thing worse. Stick with your program and continue to work at it. "Rome wasn't built in a day."
3) What would be the purpose of cutting weight?
4) Logically analyze what you did right and wrong, make corrections and implement them.
As Thomas Edison stated, "Failure means that I rule what doesn't work and move closer to finding out what will work."
Stop beating yourself up and blaming other for a missed lift.