What is wrong with me?

Physically, I feel tired, weighed down, unable to move without feeling like i'm going to collapse, and my head hurts. Mentally, I feel tired, unwilling to do anything, unable to wake myself up from sleeping, and I'm very mentally all over the place. I was soaking in a cold bath earlier but still felt hot and sweaty. I'm just so exhausted. Do you know what's wrong with me?