everyone! I started learning 3D with Blender about a week ago and now I have a problem. I don't know how to describe it, you can see it on the screenshot that I've attached. Everything started look so sharp and something like artifacts. How can I fix it? Also, suddenly the rotating of the view started rotate relatively to the 3D cursor (I think that it started suddenly). And another one problem - suddenly (who could guess it's suddenly) I wasn't able to scale the view as I wanted and I was attached to the focal view basically.
I do not know really why all of that happens and I kindly ask you to help me, please.