couple of minutes before it hits.? this will happen if i ony drive 30 minutes. its not normal. i can feel a couple of minutes before i get really tired. it's like i fuzzy felling in my body. they last between 10 - 15 minutes. i dont know what to do. i fight it as much as i can but it now its to the point i am scared to drive whith my 4 kids in the car.