Announced to close friends at 10 weeks

So last night we were out for dinner with our closest friends and told them we were pregnant. I told them I was just under 3 months so please still don't share it with anyone. One of my friends was like but your only 2 months your not supposed to tell people. This really irritated me since its your choice to do what you feel is right. I'm 10 weeks and have had an ultrasound and heard the heart beat. I don't think a lot of people understand that pregnancy is 40 weeks over 9 months.