First check in your control panel if you get an option for Pen And Touch Control.. if you have that option then try calibration of your screen..
Then try this..
Restart the pc, while the pc is booting up, tap the F2 key on your keyboard.. Your get HP Hardware Diagnostics.. Then move to components test and run a test on the touchscreen.. It'll let you know if its a physical problem or no..
Clicking Kudos! Is a nice way to say Thank You if this helped you or resolved your problem. Also " Accept It As A Solution" so that others get a benefit from it..