Just let it be: there's nothing you can do about it so being frightened serves no purpose. Even if you'd die before age 25, that's what'll happen, then accept. Use the time you have left for other things than fearing things or beliefs you can't do anything about (other than taking your antipsychotic and lowering anxiety).

Lowering your fear and anxiety will however also make your symptoms less severe. So that's really all you can do. Accept the "inevitable". If you're afraid of losing your mind, remember that you won't. Beliefs and perception may change temporarily, but it will change back to something more consistent, true. It's just a psychotic reaction to anxiety. It will get better.

Also eat well, try to sleep or rest and drink enough water or some juice or something. No black tea or coffee. If you smoke cigarettes, smoke a cigarette (or more).