Find something better to do with those 2-3 hours
The body is a crazy thing. I've gone through stretches of times when I'd function best on 4 hours of sleep. Anything more and I'd be dead. It took me a while to force myself to get used to 6 hours of sleep, which is my norm these days. Gradually, you can try and get used to more sleep if you feel your body needs it to recover, but it's not something that you can change overnight. Listen to your body and do what it says!