Like many have said I think most hunters have this 'fever' at some point. What I have found worked best for me was to have a routine that I do once I know Im going to shoot a deer.

First I "talk to myself" this gets my mine to another place other than thinkin about how my heart is racing.

I say to myself "shouting in my head"
1. ease of on the trigger
2. don't peak
Over and over until I draw

These two thingsare my downfall so this is how I deal with it. It has helped me greatly! It has taken care of my nervousness completely, and now I only start shaking and getting winded after I shoot. Hope this helps.

Good luck, you will get through it.