I've already been doing Jillian Michaels's 30-Day Shred workout every day for a week, and miraculously, the soreness from my first few days have disappeared.
Yes, I'm still at Level 1, and I don't really mind staying at Level 1 for the meantime. My next goal would be to properly do push-ups. I admit, whenever I do push-ups, I try to do modified push-ups on my knees.... When I can finally do push-ups without "cheating", then I'll move on to Level 2.
My arms already feel firmer after just one week, so let's see what results the next week will bring. 
Friday-Monday's workout
- Level 1 of Jillian Michaels's 30-Day Shred
Saturday's meals
Breakfast: Peanut butter sandwich on whole-grain bread, pastel de yema, coffee with low-fat milk
Lunch: Pork barbecue (from Ineng's), sisig (from Sisig Hooray), brown rice
Snack: Poppycock Chocolate Lovers (flavored popcorn is my kryptonite :( )
Dinner: Pancit canton, pork barbecue, brown rice
Sunday's meals
Breakfast: Fresh strawberries and roasted pistachios on Greek yogurt, pain au chocolat, coffee with low-fat milk
Lunch: Bacon and Hungarian sausage cream penne (from UCC)
Snack: Halo-halo (at Razon's)
Dinner: Bola-bola siopao, pancit canton
Monday's meals
Breakfast: Greek yogurt with dried blueberries and roasted pistachios, pain au chocolat, coffee with low-fat milk
Lunch: Korean pork barbecue, brown rice
Snack: Tall iced caffè americano with non-fat milk at Starbucks
Dinner: Pork sinigang with vegetables, brown rice
Dessert: 1 piece salted butter caramel