Scared I’m going to slip and tell close friends...

3w6d.. and have a lot of plans with several close friends this weekend/next week. I do feel like it’s way too early to tell many of them, but I’m worried I’m going to blurt it out. A few of them know we were trying and might even ask especially if I’m not drinking... I dunno if the antibiotics excuse will fly. Maybe I’m overthinking and telling them isn’t such a bad idea? any tips/advice? Should I at least wait til I officially miss my period? Haha