Don't know your dad mate, but mine used to do shit like that all the time, and they don't bother me about it now.
they still come into my room (my parents) without knocking, or knock then come straight in to catch me, but i'm too good to be caught in the act lol

You'll be ok by morning, and if he smokes, then fuck it, and if your mum has a go at you, hope your dad backs you up, or something