hi well..this may be hyperventilation syndrome
, but still some other things should be kept in mind like ischaemic heart disease
followed by a transient ischaemic attack although I don't know your age, but its a common complaint in elderly..also it may be other syncopal attack due to any cause..may be attack of glaucoma...even migraine..so please visit a neurologist
and an ophthalmologist before a psychiatrist
..have a good health..thanks..