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Sudden onset unconsciousness
and severe headache
and eye pain
may be due to a number of reasons in your age.
Infection in brain either meningitis
is most common thing we can think of these symptoms, sudden unconsciousness, fever, headache are seen, also neck rigidity
Second possibility which can we think is it was a seizure episode, seizure may present with sudden onset blackout or unconsciousness followed by headache and confusion.
Also any hemorrhage may be a possibility but its more common in elderly age.
Red spots accompanying may be due to some drug reaction or may be due to fever itself.
even if blood investigations are normal still go for repeat blood tests and visit a good doctor for management.
Hope I cleared your doubt.