I must echo what the others have said. The most important being you need to practice more. The more you shoot the less thinking about the shot process will be needed. It's called muscle memory. After thousands and thousands of shots you will just anchor in the same spot time after time. This will put your sights inline and everything else will fall into place as well. I know you said you have been bow hunting about 6 years now but if you don't shoot enough in the off season (and during the season) you will never get the practice you need.

Now as far as buck/deer fever is concerned, this is a completely different ball game. I think most bowhunters (if not all) get excited at the sight of a deer in range. I know I do, I don't care if it's a doe or a buck. Myself, I just let my emotions do what they are going to do. No matter how much I tell myself to calm down and breath deep etc... I still find my heart racing. Ibelieve this is where all the pratice comes in, your muscle memory will kick in even without you thinking about it.