Really embarring situation :(?

Ok, so I am 15 (brother) and my sister is 16. My sister came into my room asking if I had seen her ipod right in the middle of me masturbating. She just said ewww really loud and ran out. I don't know what to do because I'm scared to show my face and hope she didn't tell my parents. Should I talk to my parents about this or just leave it alone?