I find that when most snakes "lose touch with us" (ie. when we put them down, even though we're nearby) they often don't recognize us visually & may respond defensively as if we never met. Not to worry- it's normal- give them time to recognize you by your scent & touch & they normally settle right back down. Snakes are ruled by instincts- when we're just nearby, they often see us as potential predators rather than the person that just held them- they can't help it. I've seen it many times over the years, & with all kinds of snakes that were always docile when held.They just don't recognize us visually- it's not their best sense.