Am I crazy for being insecure about my boyfriend looking at a painting?

My boyfriend and I slept in a hotel the other day. In our hotel room they hung several paintings of sexy women who were half-naked and had big boobs. And I saw him looking at the paintings several times. I know it's just a painting, but I felt so anxious and insecure. I brought it up with him and he says he didn't look, that he maybe looked by accident and that he can look at the paintings in his hotel room if he wants without me overreacting. What do you think? Am I overreacting?
Updates
7 mo
I just want do be clear that the posters was of real women and not painted women
Am I crazy for being insecure about my boyfriend looking at a painting?
Post Opinion