I remember my own experiences with seroquel, and the total exhaustion was something I really struggled with. Ultimately, your medication is supposed to help, not hinder, and if it's making life more difficult for you then it's probably a good idea to book in an appointment and talk about options.

You could try a lower dose, and if you don't like it, you can always go back to a higher dose or look into other options. There are plenty of options with medication, and it may simply be that your body isn't quite reacting the way it used to.