Another thing, you can see here
that your wrist is bent back and the bar is not over your forearm. To skip over the physics talk: you want the bar over your forearm for the best mechanical efficiency.
2 other somewhat optional notes:
1. Many people, myself included, have found much improvement on the press by switching to a thumbless grip. This usually causes the bar to be in a better part of the palm, and also allows you to
slightly turn the hands in for a bit more natural of a wrist position.
2. It's really hard to see, but at a couple points in the video I thought to myself you may benefit from bringing the grip in a bit. Can you say in words how wide your grip is? I honestly can't tell very well.