Sorry to hear that. I "lost" a small buck several years ago. Looked like a good hit too. Only about 20 yrds. Thought for sure it was a heart shot. Arrow was covered in bright red blood but only found a couple drops of blood @ 20 yards then nothing. Waited for a few hours before tracking that night. We looked for about 1/2 miles radius and never found him. The next spring the farmer next property over found his skeleton about 3/4 mile away. And the deer was npt pushed. The arrow must have passed right above the heart and missed any lung. Talk about sick. I almost gave up bowhunting because of it. Luckily my buddies talked me into staying with it. Fortunately, it is the only deer I haven't been able to retrieve over a lifetime of hunting. So I guess I should consider myself forntunate. As others have stated, it does happen, sometimes even what looks like a good shot right in the vitals myseriously misses the organs. I know this as fact, I watched the arrow punch right through him. ALso, unless you see or hear a deer drop after an arrow shot, I would wait a good couple hours before looking for him/her as to not "push" him/her. Sometimes they will also try to "burrow" under brush/tall grass & weeds in the thick stuff to hide, as well as go to a water source. Just my two cents.