I've been on a diet since last Sunday. I've been sticking to a certain amount of calories daily which I know is right because I've followed Scotty K's forum about the right calorie intake. And I've been doing Shaun T's Insanity workout .The problem is.. I haven't lost a single pound since Last Sunday. I don't understand.
Go on a defecit of another 100 calories. Keep working out consistently, and get enough rest. Everyone is different. And if you don't have a lot of fat to lose to begin with then it's harder to lose. Checking the scale is not the only to see progress. You can take measurements around your thigh, arms, and waist. Use calipers to measure bodyfat. or do some pull ups, if they get easier that probably means you've gained muscle and loss fat.