Should I tell my new job im 13w?😖

So, Finally, after receiving my dream job this week! i was estatic , overwhelmed, happy, just everything above! I will now be a Family Service Specialist! working for the child protective services dept! yaayy! all my dreams came true.... then it hit me.......im 13 weeks and I really want to tell them as i am starting Monday, but im afraid 😣😣 will I even have enough vacation time built up for a maternity leave in November. I need some advice! what did you do? what would you tell your friend? 😟😟