This sounds like your arm mechanics may be a little off. I'm going to go over them fully just so you can make sure you have all the fundamentals. You're on the right track though. Arm Mechanics: Throughout the pull you want your arms to be relaxed. They should hang freely, while you maintain tension in your upper back. Once you finish your extension (which should be perfectly vertical with your chest covering the bar) the bar should travel straight up inches away from your body. This allows for the elbows to track vertically instead of back. All these things are great, but if you're leaning back in your finish the bar is going to get away from you regardless. Work on your finish and these arm mechanics and everything should improve. Some high hang work should do the trick. Fear in the setup is a tough obstacle. It's really hard to execute great technique if you're not confident that you can make the lift. All I can say is that you need to get tight and already have 75% of the bar lifted before you start the movement. What I mean by this is that everything is engaged a nd tight before liftoff. Then hold position, be patient, and finish hard. Mindset is a huge portion of weightlifting and you will have to learn to believe you can make lifts! The more you do it the more confident you will get. Try doing waves or maybe even sessions where you take 6 sets of 1 at 85-95%. I hope you find this helpful!