I had that happen in WY while calling coyotes. 10 head of deer came flyin up the hill to us. For a second, I thought we might get trampled. Most of them stay 10-20 yds behind us for the entire set (20 minutes). They could see us and smell us, but that instinct to protect kept them around.
That buck looks young, he might be a nice one if he can stick it out for a few seasons...