I agree with Hillybilly and bwhunter. If you couldn't find the arrow, there is a good chance it did not go all the way through her. I had this happen with a mechanical I was shooting earlier this year. I shot, knew I had hit the mark, but no blood or arrow. Luckily, I waited patiently and heard her fall so I knew the general direction to head once I made it to the point where I lost sight. When I got to the deer, the arrow punctured just behind the right shoulder but lodged in the bone of the opposite shoulder. No blood till I pulled out the arrow, then plenty - although too late by then.