Husband tells his family we're expecting without me

I'm so mad! My husband just told his parents and sisters that we are expecting a baby and I specifically had asked him not to because we wanted to surprise them TOGETHER! I'm at work right now and I'm so upset I can't get over it and now with my crazy hormones I can't stop crying. It's upsetting because his family is DRAMA and I'm so mad that I haven't even told my parents or siblings who have been super supportive of us and yet he goes and does this. Am I overreacting? I know I need to stop being mad but it pisses me off knowing he did that. To top it off he has like 8 brothers and sisters who will now know before my family. Any advice?