Cursor moves while changing camera-angle

I ran into this problem; My cursor doesn't stay in the same place when I change the camera angle with right clicking on mouse, it used to stay in the place where I started to hold right mouse button and then drag mouse in any direction, and I haven't changed any settings, and I went through the settings and couldn't see anything concerning 'bout that.

So I'm asking, if anyone knows how to fix this.
Thank you.

Edit:
Well, if I alt-tab to other window and alt-tab back, the cursor stays at the place, BUT if I: A) Move B) activate Chat C) hold both, left and right mouse buttons (move forward) it breaks again.

Edit 2:
Seems like shutting down and restarting computer fixed that. It's been working today.(25.2.2014)