I think hes mad... or am i just being over sensitive?

so last tuesday me and my boyfriend got into a convo about hanging out the next day and he told me "ill make sure i can go but i have a doctors appointment." so i said ok let me know after school. he agreed tht he will let me know before 430. so wednesday rolled around and i waited and waited and 530 rolled around and he hadn't texted me. so i texted him he told me he was at the gym leaving to go to the doctors and then to play ball with his buddy. so i asked if he had forgot about our plans. he got defensive saying that he told me he couldn't hang out with me cuz of the doctors appointment. when i called him out and fwd his own message about letting me know he backed off... today is saturday and he hasn't really talked to me since thursday. hes been very stand offish one word answer messages.. he doesn't answer my gnight messages or anything... am i being over sensitive or is he mad at me?