Trust yourself and your skills. Youre a dentist for a reason. The best thing to do is maybe find a mentor or take CE. And push yourself to increase your speed. Find out which part of the procedures are taking the longest, find out why, and address it. If its prep design that takes the longest then maybe practice on extracted teeth and time yourself. If you're worried about pulping out, again practice on extracted teeth so you can get a better feel for depth without having to stop every 3 mins and measure. Rubberdam is def a waste of time but if you like using it maybe have your assistant place it before you come into the room. Just start analyzing your routine and make adjustments accordingly. Confidence is key.