30 day shred... can I do this?

I recently purchased Jillian Michaels 30 day Shred. I did the 30 day Shred for the first time today, I thought I was going to die. The thing is I know that my muscles will hurt even more tomorrow morning! I am committing myself to doing this for 30 days, its only 20 minutes a day and there are three different workouts so when I get bored or the workouts get easy (which I am not betting on happening) I can switch to another workout. I can't help but think, "A 30 day commitment to a exercise program... can I really do this?" We'll see I suppose!