I use a 100 grain Wasp boss sst. It's a 3 blade fixed broadhead. When a deer is quartering to you the margin for error is high. Your shot may have hit right where you were aiming but a deer only has to move inches for it to turn out wrong. Some shots whether with a gun or a bow they just don't bleed right away. Now your deer probably once his chest filled with blood then he started to bleed. May have been 150-200 yards from where he was shot but once the rain set in, without being able to use a dog, you were screwed. Get you some lighted nocks so you can see exactly where the arrow hits. This will give you a better idea of whether you need to go after him right away or give it time. I can't say that I wouldn't have taken that shot my self but you want to aim for where the arrow will exit. Odds were against you this time but who knows you may get another chance at him. Without a recovery there's no guarantee you killed him.