Is my brothers friend mad at me?

My name is Sarah my brothers friend CJ is down for a month this summer but I am leaving for the same month so we won't be able to spend time with each other and I think he's mad at me cause the day after I said it he went to another friends house. At one point we were together but it didn't last long and when he was here two summers ago we were kinda flirty with each other. I want to spend time with him before I leave but I don't know what to do I have a hard time expressing feelings and I am always nervous when talking to people. Please help.