My nephew walked in on me !

My 13 year old nephew walked in on me pleasing myself . Our door doesn’t have a lock but everyone knocks before entering I always do it under the covers but since we live in Hawaii it’s so hott I quickly pulled my legs toward me so it looked like my shorts were rises up. I’m not sure what he saw because I was in my zone I’m so embarrassed I don’t know what to do. He’s kinda of a troubled kid so he was most likely high but still