I have what feels to be a odd symptom. I will feel full of energy and physically fine while working or sitting in a car for a long car ride but as soon the day is over or I lay down to rest it feels like my nerves unwind. I become weak, I feel like my lungs become weak with no energy to breathe, my body heats up really hot and sometimes it is very scary feeling so weak. After about 30 min to an hour or more depending how much I exerted myself. I feel mentally exhausted from my body heating up. This symptom gets worse in hot weather. I will usually experience exhaustion and shaky nerves for a few days afterwards. This also happens after a shower sometimes. Is this really part of panic or depression?