Freaky squirrel

So this is a random post but there is a squirrel seriously determined to come in the back sliding glass door. I'm sitting in plain view, literally 6 feet away and this thing is looking right at me as it bangs its little squirrely fists against the door. It is freaking out in a very human way. It even looked like it was feeling along the edge of the door as if it could get a paw in and slide the door the rest of the way open. Remember that scene in Ghostbusters where Rick Moranis is running away from that devil dog thing and he's banging on the window of the restaurant but no one see anything but him? That's this squirrel. There is nothing else out there, I just checked. And the squirrel wasn't afraid of me, it just kept freaking and trying to get through the sliding door. Which is glass. And is closed. Funniest thing about this? When it first started, it almost sounded like knocking, to the point where I looked over expecting to see the guy who had been working on the gutters for us. But instead, I look over and it's a squirrel.