Changing room masturbation

I hope this is the right place to post this but a few days my family and i went to go try on clothes and buy some. My brothere went in first and was asking if we liked the shirts and stuff but taking a long time which is understandable but i went in after him and clothes were on the little chair there so i moved them and it felt warm and wet and i looked at it and he came in them. I was shocked but i moved them aside, should i have done something different besides move them aside and could he get in trouble?