Lisa don't be scared! Just little hiccups, you've had some great advice here and I expect you will get more. I tried it for the first time the other week. I found it helpful to practice the stipple pattern with a pen and paper beforehand, kinda gets your head used to what you need to do.
Keep tweaking your machine settings until it works. Then right down that ideal setting so you will always know what to go back to.
Good luck, am sure you'll do fine.