1st pregnancy super nervous

I am 20 turning 21 this year and i found out 3 days ago i am pregnant!!!! But the night before i found out i had drank a margarita and a beer and a half. Im super scared that my first will end in a miscarriage as ive been trying for about a year and a half now. I've never been they happy and or excited for my future. Can any other mommas give me some insight on just how to like idk not be worried and just let what ever happens happens??? Also i have taken 3 pregnancy tests on the 16th (640pm immediate line) 17th( 8 am immediate line) and 18th (today 8 am immediate line)