Dota 2 broke system resolution?

hey guys thanks for reading,

so whenever I play dota 2 i play with 1 of my 2 21 inch 1920x1080 monitors, I have my friends oon stea, and precsion X, on one of my monitors and whenver I open dota both screens turn off for a split second and the stuff on monitor that does not run dota items move over to the left. 

Today when I went to go change my resolution in Dota 2 my backround picture literely shrunk to about 17 inchs instead of its original 23 inch backround of my 2 monitors. All i did was change the resolutiuon for 1280x 768 to 1920x 1080 , when I did this with other games it never affected anything but the games resolution, I tried to revert dota to it's previous resolution to fix my backround but its still shrunk D: i tried other backrounds that were 1920x 1080 but they still are at about 17 inch and surronded by black, however I still have my icons on far right htey still remain insame place can comeone please help me ;~;