Help with quince (Sweet 15)?

So my friend asked me to be a dama for her quince. And we've been going to practice for a couple months now, and her party is July 23. And we are getting our dances from youtube videos! We arnt learning anything. She doesnt hire a coreographer. And Im super worried were not going to learn the dances in time for her party! I am super nervous. The practices arnt set on specific days, there all random. So my mom gets very upset with me because she asks me if i have practice that day and i never know! No one wants to be in the dance anymore. And I dont either, but im not going to quit because i told her i would. you know? And we still need another dama and chambalon. And Idk what to do! We have to learn like 3 or 4 more dances still. And we learned 1 during the past 3 months. We have practice 3 times a week. OMG! What do I do? I dont wanna be a dama and look like an idiot the night of the party. Can you guys please give me advice? I speak a tiny bit of simple spanish, so if you could write english please. i have a hard time understanding it. (dont take that the wrong way!) Thank you so much! And about the youtube videos dances. They arnt teaching it to us. We have to watch and dance. So we pause it and rewind every 3 seconds. Literally. And we arnt getting anywhere!!! Ahh Im so stressed! I want to quit but it would be terribly rude to my friend! What would you do?!