I just shot my first deer ever, too, Rick, and i had the very same thought as you, "Oh S*&t, i just shot a deer." Shot him on the ground, from no more than 15 feet away, with a 4-bladed 125 on carbon shaft, using a yew longbow i just finished. I was able to stalk that close to him! As soon as i loosed the arrow, the buck bounded away. I am sorry to say i could not find it. It still bothers me. I had bad dreams that night of wounded animals. One was a huge horse with my arrow poking out of his shoulder! Another was my buck but with a whole pile of my arrows in it. Another, of all my arrows stuck in a post off the property.
Next time. You did good, buddy.