Anxiety / panic attacks

I suffer with panic disorder and it drains me so much and just want to sleep

I’d say that’s about right. It takes so much energy for the body to be anxious. During anxiety/panic, our bodies go into hyperarousal aka survival mode (fight/flight/freeze) which diverts all of the body’s resources to staying alive, even if you’re not actually at risk of dying. Once you’re finally through the panic, the body is depleted of energy and needs to recoup with rest and sometimes food. It’s not uncommon to feel exhausted and hungry after coming out of a long period of anxiety or a panic attack. Hope that helps. Take care of yourself!