I'm feeling burnt out.
C2I'm exhausted and emotionally drained due to prolonged or excessive stress.
My nerves are frayed.
C2I'm extremely irritable and easily agitated due to stress.
I'm experiencing a significant amount of mental fatigue.
C2I'm experiencing extreme mental tiredness and exhaustion.
I'm at the end of my tether.
C2I'm at my limit of patience and coping ability.