hi I have question: Scratch Disk Full

Hi I am using adobe photoshop just few days ago and I already pay for it so I opend it and it was work but my computer said my macbook have scrach disk are full so I mannged already and other Adobe is works fine but only photoshop is not open and keep saying scarch disks are full. I am not sure why only photoshop is showing me that.... I am actually web desgne student and I am using photoshop adobe alot. could u plz give me how to figure it out?? thank u.