What Causes Severe Headache,unconsciousness And Feeling Confused?

i woke up monday morning whent down and fed the kids, told the wife i had a headache and had a shower next thing i no its tuesday afternoon. my wife said that i collapsed on the bedroom floor for about a minute and then complained of a terreible headache, she took me to the hospital and i was talking rubbish and seemed very confused as to what was going on they did various tests and nothing was amiss this is now the third time this has happend i am only now starting to feel normal again and yestersday i was very emotional?