I want to see if other people experience daytime sleepiness in this manner?

First of all, no, I do not always get my eight hours of sleep. Usually, it is about 6 hours, but I want to see if people who experience daytime sleepiness have a similar experience. Do we experience the same? Does the sleepiness hit you abruptly? This is how it starts for me: I am usually wide awake and very alert then out of nowhere it comes over me like a wave. I can feel it coming but it is usually full blown in like 3 minutes or less. I've always questioned whether I have narcolepsy or something, but the thing is I can stay awake if I fight it really hard. Most commonly it happens in the afternoon, but can happen in the mornings around 9:30a.m or in the evenings around 7:00 or 8:00. The two most common activities I am doing when it happens is driving and reading. The driving is really the part I want to ask about. I will be fully alert before getting in the car and sometimes during the commute it will hit. It gets worse and worse but I manage to stay awake, but everything gets like dreamlike (almost like derealization). I am aware of what I am driving, I know where to go but thoughts kind of get scattered, racing, and strange and everything just seems really weird and confusing. It takes everything I can to stay awake. Sometimes my eyes will go cross-eyed where I am fighting it so much. Sometimes I wonder if I am actually sleeping in a semi-conscious state. When it comes to reading, I try to fight it, but I guess because I know I'm not in danger, I just lay my head down and I'm out for 15 to 30 minutes usually. I've also been writing before and continue to write, usually not staying on the line. If I sleep it off or fight it long enough, it eventually goes away, usually going away almost as sudden as it came. Another thing when I get done driving it can still stick around a little bit when I'm walking where I need to go. I know not getting enough sleep is probably a big culprit, I just don't understand why when I have gotten like 2 hours of sleep, I can feel alert all day but I can sleep 10 hours and it can still hit me. Anyone have a similar experience? Is this normal? Am I just being a hypochondriac.