What Causes Severe Fatigue And Dizziness?

Last night I got a full 8 hours of sleep. This morning at work, I suddenly became so fatigued, I felt like I d been shot with a tranquilizer gun and like I was going to pass out. I became very dizzy and actually tearful. I was well-rested, well-hydrated, and had a morning snack that was high in protein, fiber with adequate carbs. As a nurse, I went to my boss, went to our recovery room and laid down. BP 124/70. I then became photophobic and my head began to hurt. It was unlike my usual migraines. Pressure behind my eyes, then to the top of my head, then to the back of it. I got a ride home. I felt so weak at this point, I didn t feel like I could move. I laid down and fell asleep for 3 hours. Woke up, head still hurt, and fell back to sleep for another 3 hours. It is now 11 hours later. I still have a headache, but was able to eat dinner. Still feel like I could sleep more. It seems a bit difficult to have a deep, filling inhalation but I don t feel short of breath. Is this just an odd migraine presentation?