I’m glad to hear that she’s okay.
I would watch her when she gets shots and other procedures in the future - even when she sees blood or some other person getting a shot.
That reaction is called “vasovagal syncope.” http://www.webmd.com/brain/understanding-fainting-basics
Fainting can look very dramatic, with all the automatic movements and the “eyes rolling back in your head.” It’s more a blood pressure event than a true problem in the brain.
The subconscious seems to decide it’s time to check out as a “fight or flight” reaction to perceived danger. The brain sends messages to the heart and the blood vessels to cause the blood pressure and heart rate go down and people completely pass out. It’s completely out of conscious control.
As long as they don’t hit anything when they fall, there’s no left over symptoms after the adrenaline wears off.
I’ve had watchers, dads and friends, do the same thing. Moms will sit when I ask them to, but not all dads will, so they faint more often than moms, it seems.
I just got woozy reading that post! LOL