I'd be well pissed off. But then I am super-possessive. If you're worried about it, ask him. You had a valid reason for being in his account, so it's not like he has any ground to be pissed off at you about it. Plus, in my experience, if something like that is getting to me and I don't mention it, it snowballs, and then we have a huge row over it, whereas had I brought it up earlier, we probably would only have had a minor tiff xx