I honestly really don't remember much of my life until around the age of 22. It was just a blur. I have piano compositions and orchestral pieces I wrote in my teens that I know I spent hours and days on, but I don't remember actually writing any of them.
I hate seeing home movies from from my childhood because I was burning at 115% in every single one of them, all of the time. I honestly don't know how my parents put up with it. I would have killed me.
Today, at 37, I'm exactly like you describe: I'll work in a flurry of energy for 4-6 hours, get everything done and then coast for the rest of the week. I've also been successful, I'm a Director of IT but the VP I report to is exactly the opposite of me, he works slow and steady the entire week. It's really bizarre.
G-d forbid. If only your Mom had the insight to dope you up with Ritalin or Adderal (unless you were Canadian; Adderal is BANNED up there)...she could have suppressed all of those inconvenient bouts of creativity. :-)