His mother caught us naked!

Vane
Yesterday me and my boyfriend, for almost 8 months now, had sex in his house. When we finished we cuddled naked for a while and in that moment his mother entered the room and saw us both naked. She laughed, apologized and closed the door and I did not know what to do, i am really embarrased with her. Me and his mother have (or had) a really good relationship and Im worried that is ruinned because of that, I am really ashamed and i think i wont be able to see her again. 
Help please, what should I do?