What do you think

So my best friend just called me and told me that my boyfriend has hit her up a few times asking for weed and not to tell me about it. As much as I would like him to not smoke I never told him he can't and he hasn't tried to hide it from me. So I don't get why he is telling her that I told him not to smoke and that he needs weed and not to tell me. On top of all that he told her that I thought he was at work. Am I getting upset over nothing or does it seem like he's just trying to find a reason to talk to my best friend...