Strip Club

So my boyfriend is on a stag do right now. I trust him but recently a few things have happened that have made me question his loyalty to me. I've found a picture of another girl in a bikini on his phone, it was faceless and the girl had sent it to him of her body and it was in his gallery so he had saved it. I then looked at his internet history and surprise surprise there were a million porn videos. I've spoken about these things to him and he's deleted them and swears his loyalty lies with me and that he doesn't need to look at other girls - which as you can guess I find very hard to believe. Anyway, I'm scared that tonight he'll go to a strip club despite promising he won't and pay for whatever with one of the girls and I have no way of knowing because I think he'll lie about it. I don't want to be crazy and check his phone I just want him to be honest with me