Headache might be caused by a number of things including tension, anxiety
or some times fluctuating blood sugar
levels. Eye problems can do this too.
Dizziness may be associated with your headache or it could be from inner
ear problems. Lower abdominal pain
could be from constipation
retention. Nausea can go with headache.
Serious conditions such as brain tumor or abdominal epilepsy
Low Iron can make you feel tired and week and can cause dizziness .
Hope your doctor will do the right kind of tests to help you.
Wish you good health.