Cursor has turned into a tiny dot

Hi, my cursors has turned into a tiny 1 pixel dot,

its currently only happens in one file, doesnt effect my desktop (googling suggests could be a system thing)

and id like to revert it back, its near impossible to see where it is and where im hovering over to work effiencetly,

i havent attached a photo as its pretty impossible to get it to show obviously in a image