boyfriend jokes around :(

My boyfriend jokes around all the time and he gets a big smile on his face. For instance he was looking through my history on my phone and asked me why I have photo director downloaded on my phone. I told him well duh to edit my photos that I add to Facebook every now and then and he said oh well why do you need to edit your photos. Are you sending your photos to other men. I looked at him and became upset and he made me cry cause he always says things like that but has no reason not to trust me cause I am so faithful to him and never talk to other men. When I ask him why in the hell does he do that to me he just says it's who he is or else he doesn't know why. He then says that he doesn't mean it either or think that I am doing any of those things. I am puzzled cause why would he say something if he doesn't think that I am doing anything wrong? I can't even dress nice every now and then cause if I do then he questions me and if I put photos of me just on Facebook he asks me why.