The symptoms this individual describes are most likely due to migraine headache (migraine without aura, also known as common migraine). Migraines are diagnosed by the following criteria:

• More than 5 episodes (lifetime)
• Headache lasts 4-72 hours
• During headache at least one of the following:
• nausea / vomiting
• photophobia or phonophobia
• Headache has at least two of the following characteristics:
• unilateral
• moderate or severe pain intensity
• pulsating
• aggravation by normal physical activity, may cause avoidance of normal activities of life
• Not attributed to another disorder

The symptoms described by this individual make tension headaches the most likely diagnosis. Tension headaches are defined by the following criteria:

• Minimum of 10 episodes occurring on less than 15 days per month for at least 3 months
• Headaches last from 30 minutes to 7 days
• Headache has at least two of the following qualities:
• mild or moderate intensity
• bilateral
• pressing or tightening (non-pulsing) quality
• not aggravated by routine activities of daily living
• Both of the following:
• no nausea or vomiting
• either photophobia or phonophobia, but not both
• Not attributed to another disorder

The presentation of this patient's headaches would make cluster headache the most likely diagnosis. Cluster headaches are defined by the following criteria:

• At least 5 attacks
• Severe unilateral orbital, supraorbital or temporal pain lasting 15-180 minutes 
• Headache is accompanied by at least one of the following:
• ipsilateral conjunctival injection and/or lacrimation
• ipsilateral nasal congestion and/or rhinorrhoea
• ipsilateral eyelid swelling
• ipsilateral facial sweating
• ipsilateral miosis or ptosis
• restlessness or agitation
• Attack frequency ranges from every other day to 8 per day
• Not attributed to another disorder

While caffeine may be a migraine trigger for certain individuals, in the majority of people who experience migraine headaches, caffeine provides significant relief of pain. This may be due to it's antagonizing adenosine receptors, which has the effect of cerebral vasoconstriction. Caffeine withdrawal, however, is a common cause of headaches and may trigger migraine is susceptible individuals. Other common migraine triggers include food allergies, medications, bright lights, stress, lack of sleep, hormone fluctuations, strong odors, alcohol, and certain types of exercise. 

Atonic seizures are characterized by brief (2-15 second) loss or lapses in muscle control, resulting in sudden relaxation of the neck, legs, or whole body. This seizure type frequently causes injury due to falls or head trauma. There may be spasm or twitching at some point during an atonic seizure, but they generally present without any form of rigidity or clonus, unlike tonic-clonic and myoclonic seizures. Atonic seizures differ from absence seizures in that an individual experiencing absence seizures will generally only experience a loss of consciousness, without an accompanying loss of muscle control. 

The "aura" experienced before a seizure, while frequently thought-of as a primarily visual experience, can include disturbances in taste or smell, bodily sensations such as stomach ache or tingling, anxiety, or a sense that everything is oddly familiar (déjà vu) or unfamiliar (jamais vu). 

A generalized seizure is one which involves both sides of the brain simultaneously from onset and results in loss of consciousness. This is contrasted with complex and simple partial seizures, in which only one area of the brain is involved and the individual may or may not lose consciousness (in complex and simple partial seizures, respectively). Seizure activity that lasts for 30 or more minutes is a rare and serious condition known as status epilepticus. Any seizure that lasts for over five minutes is considered a medical emergency and requires emergency assistance.

Currently there are over 40 distinct types of seizures recognized by the medical community. Some of the most common seizure types are generalized tonic-clonic, absence, myoclonic, clonic, tonic, febrile, and atonic. Some other less common types include refractory seizures, gelastic seizures, and dacrystic seizures.

Absence seizures are typified by a brief, 2-30 second loss of consciousness in the absence of other symptoms. Individuals with this condition generally will not experience muscle rigidity (as in a tonic seizure) or jerking (as in clonic or myoclonic seizures), nor do they experience a loss of muscle tone, as seen in atonic seizures. Absence seizures present frequently in young children as "staring spells" and may cause issues with learning or appear as inattentive behavior in school until correctly diagnosed by a medical professional.

While CT and MRI may aid in discovering structural abnormalities associated with certain seizure disorders, the correct tool for diagnosis of seizures is electroencephalography (EEG). An EEG can show abnormal surges in brain activity responsible for temporary loss of consciousness in absence seizures.