My touchscreen is tapping the corner of the screen

Every time I turn on my dell inspiron duo, the touch screen starts acting up. it is constantly "pressing" the corner of the screen on its own. because of this I cannot complete any tasks on it because it closes everything out and the cursor always goes to that corner as if I were constantly touching the corner. Nothing is on the screen making it do this. It has done this since a few weeks after I got it. It was given as a gift so I don't have the receipt or anything to go with it to send it off to dell to get it fixed. Please help.