Hot weather, bathing in hot water, lying in the sun makes me feel sleepy & hallucinatory. Feel weakness in my muscles and cant sleep. I drink enough water?

Possible. if you sweat a lot or have change in urine color may seek urgent or ER may have Rhabdomyolysis. Drink more water.
Other symptoms? do you have numbness, tingling over any part of your body that persists or is new? Any of these problems when weather is cooler or cold? How hot do you like your bath or shower water? Any butting of vision in hot weather?