Mouse movements go in wrong directions

This happens only in CSGO. When I am playing and I try to flick right or left quickly it often makes me stop moving my pov left or right and slings me the other direction and or down. I do not know what is going on or how to fix it.

I have tried a different mouse but it does the same thing.

How can I fix it?

Sometimes having a secondary monitor can mean that the mouse tries to track on that screen however I would make sure your drivers are properly configures or download someone elses config except swag's since he likes to mess around with mouse accel. Change to your sensitivity then see if the problem continues, also if you have a logitech mouse the "mousepad recognition software" can cause plenty of tracking issues as it did for me.