I had so many thoughts and then that last scene happened! I was surprised they went with the blood spray onto Buck, that's brutal. Obviously the sniper is targeting first responders because they had a clear shot on Buck (not in uniform) and moved to shoot at the other guy (in uniform). I am really hoping they don't make Christopher an orphan.
Other storylines - the AAA is definitely deadly if it ruptures, I work in blood banking and usually ruptured ones don't make it to the hospital but if it ruptures at the hospital or in surgery, those patients use a LOT of blood products and still don