headaches... from handbook of signs and symptoms 3rd edition by sundaram ramanan pp309-314:

The headache is the most common neurological symptom. They may be localized or generalized, producing mild to severe pain. About 90% of all headaches are benign and can be described as vascular, mucsle-contraction, or a combination of both. Headaches can indicate a severe neurologic disorder associated with inflammation, increased pressure, or irritation. They may also result from a sinus or ocular disorder, tests, drugs, dehydration, eyestrain, fever, or metabolic disturbances.

Here we are looking at the headaches being indicative of a problem with acetaminophen use combined with marijuana use and heavy drinking (possibly dehydration of a hangover).