Waitlist

Hey I have horrible anxiety and idk what to do. So I’m waitlisted for three courses, one is online.

Should I email the teachers a week prior to class letting them know I’m on the waitlist and just ask if its ok for me to sit in class on the first day?

What happens if i arrive early to the class and get a spot but then there isn’t enough seats? Do I awkwardly have to get up and leave so the registered students can sit?

If I do sit in the class do I talk to the teacher at the end letting them know I’m waitlisted?

If i still am not registered in the 2nd week do I attend the class again?

Sorry if these all sound dumb I’m a new-ish student and this has just been frightening for me.