Bear with me on this one cause I may sound crazy. But when I was constantly doing bjj I made a note of the paterns and performances of my training. The days I ate junk I performed terrible and the days I ate clean I would perform a little better. One day I was feeling super insecure, depressed, and sad because I doubted myself. I have dreams I want to accomplish that involve bjj and I felt that I would never get them. I asked myself why am I trying and it'll never happen and all that negative shit. That day in class some new kid kicked my ass. He passed my guard, maintained positions, and even went and almost finished the armlock we learned that day. I was a two stripe white belt at the time and I almost quit that day. But the very next day I went in with a positive attitude, maybe even a little cocky. I told myself I was gonna be, if I'm not already the best bjj fighter in the world at my level. I convinced myself that I truly believed it. I performed very well that day. I swept like two blue belts, tapped out a 4 stripe white belt, and that kid who kicked my ass got tapped like 3 times. I truly believe your mindset mixed with a little bit of autogenic conditioning can you make you perform so much better.
Edit - also instead of learning particular techniques, try to learn and understand the conceptual part of it. That helped me a ton also. Good luck man and believe in yourself. "He who says he can, and he who says he can't, are both usually right."