Still need more info. You thought it was a good hit...why? What was the deer's angle to you. Broadside? Quartering-to or away? Steep downward angle?
Were the blood specks directional? Maybe the blood didn't really quit, maybe she doubled-back and changed direction. Blood spatter shows the direction of travel.
What was the height of the blood? Any high enough that would show it was blowing out of the nose/mouth? Was the blood on both sides of the trail or just one side, and how far off the trail was the blood? Arterial bleeding tends to spray out farther but those deer usually die quickly...just a few things to look for when blood trailing.
Did you use peroxide to help locate blood?
How many people were trailing and were they walking on the blood? Too many trackers is not good and never walk on the trail.
This a a prime scenario for using Luminol as a last resort. But even with that amazing stuff, it won't find blood if it isn't there. If a wound gets clogged with fat or guts, no external bleeding may occur.