pen tool making selection of entire artboard..

Hi 

I am in the middle of editing photos onto white backgrounds and am using the pen tool . Now all of a sudden when i make my selection with the pen tool it decides to delete everything that is not in my selection. I have tried re-setting my settings , updating photoshop and re-starting my computer. I can not figure out where the issue is coming from and how to change it. If anyone can help me out i really appreciate it! Thanks.