Sorry, it is not much information.
Let me share my points about your condition.
It is very unlikely that food poison has worsening of symptoms in the specific time “between 5-6 am”.
More reasonable to suppose connection with your sleep and lie down position.
Bad sleep position and high pillow can strain your neck spinal column causing spasms in the neck, hands, even upper stomach area, and headache.
Next, less possible, is hypoglycemic attacks at night with headache, spasms, cravings, or changes at night in calcium and magnesium
level in the blood.
If I were you, I would change the pillow, receive massages or chiropractic adjustment, take magnesium/calcium supplements
, eat proteins
before go to bed, and drink chamomile tea at the evening. Weight and see.
If it will not help, you need evaluation from your doctor.