boyfriend

Okay so me and my boyfriend have been together for 2 years today ! Whoowho!! Right ? Well there is a problem well to me I don't have facebook never really care for it but he has a fb he has one of my cuzions on there and she sent me a screenshot that he just recently updated his profile pic to one of this girl she looks about my age 21 or younger and he's 25 so he changed the profile pic to her and it's making me question who is she why he put her there like is there something I need to know what should I do I'm going to talk to him about it but no lie my heart hurts like when you've been let down