How long until I see results?

Ok, I've been doing Zumba since Saturday and been going for brisk walks. I've been doing the live zumba DVD seeing as my mum lent the others to my aunty. I've been doing 30 minutes a day, but today I did an hour. I just want to know when I'll see results, I at least want to lose a dress size. Also hoping to drop 10 kgs. Can anyone tell me their experiences with Zumba? I'm going to keep going but I just like hearing peoples stories in order to feel even MORE motivated, thank you :)