Agree, eye relief and make sure you didn't turn the scope at all and the crosshair's are still straight up and down. Doesn't take much to get them off line. Since you have not sighted your rifle in moving the scope back won't affect anything. That Nikon scope will give you 3.6 inches of eye relief so hopefully your cheek weld won't put your eye to close. If needed you can always get a cushioned slip on butt stock pad that will help you out. Let me know if you have any question's about your scope.
My name is Bart, I am a longtime hunter and I am here to answer any questions on Nikon hunting optics you may have. I will also be sharing new products and specials on occasion.
Nikon Pro Staffhttp://www.nikonhunting.com