Yeah of course it's gone. You took a drug that takes away anxiety. It has the same effect on pretty much everyone. You're not special. The drug will wear off and you will go back to having anxiety. Unless you take it everyday, but then the same dose stops having an effect, so you up your dose, and then guess what? You're addicted. It does NOT take long to get addicted to benzos. 3 days in a row is enough to become addicted.
The way you're feeling right now, you're probably thinking to yourself "If I could just remember how I feel right now and apply it to when I'm not on pills then I'll be cured" .... yeah.... no. That's not how it works. You're not going to figure out what changes in you. You already said it yourself. It's the chemicals in your brain that have changed. The drug will wear off and you'll be back to where you were before. Good luck though.