Don't stop now!! If you're not weighing yourself, then it's going to take a while before you see any changes. Even people who do weigh themselves regularly and see the number drop don't necessarily see a difference when they look in the mirror.
I've been doing this for a little over a month now, and I see absolutely zero difference in my flabby arms, bulgy stomach, and huge thighs... but I know I've lost 10 pounds, which is great for a month! I'd never guess it from how my body feels though. I think it really takes closer to 15-20 pounds before you really start to see a difference, and that can take a couple of months.
So don't worry, you're on the right track, and I'm sure you're doing much better than you feel! Just keep on tracking your calorie intake honestly, walking to class, and you'll start seeing a difference soon enough.