I just have one last night. I have to use a paperback. Then happens again late at night so I took clonazepam, that is prescribed to me for situations like this.

Google:
You can try some immediate techniques to help treat acute hyperventilation:
Breathe through pursed lips.
Breathe slowly into a paper bag or cupped hands.
Attempt to breathe into your belly (diaphragm) rather than your chest.
Hold your breath for 10 to 15 seconds at a time.