I don't see anything wrong with shooting at a moving deer. I have killed deer on the run with my rifle a few times. If I'm comfortable with the range and the deer isn't moving too fast I have no problem shooting. I have also made good shots on deer and they didn't just fall over. I won't just let the deer walk off and die like they do on the hunting shows, I put another bullet in it. Everyone makes a bad shot sooner or later. If you can honestly say that you tried your best and you took a shot within your skill level you have nothing to feel guilty about. A deer that is hit badly will most likely die a quicker death than it would have if left up to nature. Loosing sleep and feeling guilty about a bad shot isn't going to do you any good. Just trynot to make the same mistake the next time.