I will take a look at the video. Mentally I want to play in these tournaments the same way I play in practice and want to rid myself of double faults like the one I posted. It wasn't just my serve though. My return was way off and I missed a ton of volleys and my backhand went back to my old technique as well. Looking at the videos of myself it was like all the work I've done the past few years was for nothing.
First thought - I appreciate your honesty here. This is a miserable feeling you're describing and I've definitely been there myself. Probably several of our pals here can feel your pain. I've had some really good coffee this morning, so here goes...
I routinely recommend Vic Braden's book, "Mental Tennis", to our pals here. Everybody has their favorite - maybe "Winning Ugly" or "The Inner Game of Tennis". But this one by Braden helped me with making profound improvements both as a player and as a coach. You can get it in paperback for only a few bucks.
As far as wanting to play in these tournaments the same way as you play in practice, the good news and the bad news are sort of the same news. You need to practice with the same intensity and focus as you need for playing well on match day - not many of us can do that. When I'm coaching my teams, I'm routinely chirping at the kids to embrace this thinking when they're sort of coasting in the middle of a practice. If we're having an easy knockaround and hitting every third ball on two bounces during practice, all we can recall on match day is mediocre, right?
Take a little comfort in the fact that it might be impossible to completely achieve match day focus when practicing. On the practice court, we can turn our mind's eye on ourselves to some degree, but during a match, most of our focus is shifted toward what's happening on the other side of the net. Anything we recall has to be ingrained enough that we can pretty much do it without thinking about it.
If you are sometimes falling back into your old technique - you mentioned your backhand - that's because you haven't gone all in on your new technique yet. Sometimes that can require twice as much work as we might think to truly make those alterations and develop our games. Maybe that's why some wise coaches like to encourage us to "enjoy the process". We never know how long it takes until after we make the changes.
I could probably only help with the technical aspects of your serving if we were on the court together with a bucket of balls, but I'm not just thinking about the nuts and bolts of your move on the ball. I want to know about the "when I get nervous in a tournament" situations. Are these coming whenever you have to hit a second serve, when it seems like you've arrived at a make-or-break moment (set point, break point, etc.), or something else?
If your slice serve is more reliable than your kick serve, use your slice serve, especially when you need to land a second serve. If your kick serve is less reliable, use it for an occasional first serve, but not so often that you're wasting too many first serves. Get more first serves in. They're not throw-away chances at free points - trying to whack aces that only miss over and over again. They're opportunities to avoid having to land second serves.
Do me a favor; re-read post #15 and ask yourself whether all those thoughts are going through your head when you're practicing and not when you're playing a match. I'll bet you a nickel that they're not happening in practice. That's a big tip off that your expectations of yourself on match day are wildly different than they are during practice. If you can't live up to those higher expectations when playing those tournaments, you'll be doomed to constant frustration and playing too tight too often. You need to confront them. This is straight from the wisdom of Braden. Get the book, it might just change your life