Telling my mom

I recently found out I am pregnant. My husband and I are very excited but I'm scared because I have a really bad pain /cramps on my right side . I have an appointment scheduled for this Wednesday. My husband thinks I should tell my mom now but I'd rather wait until after the appointment. My mom gets so excited about things and I would hate to tell her and then (God forbid) the pain is an ectopic pregnancy or something. Do think I should I should tell her now or wait until after the appointment?