Hi!
I hate to say it, but your mother is probably right. It is possible that the stress from your recent illness caused your ovaries to "forget" to ovulate and that has resulted in this extra heavy period. If this is the one and only time you have a problem, then, no worries. If you start having "Extreme" periods frequently though, it might be a good time to check in with your mother's doctor. It can sometimes be a sign of a bleeding disorder such as Von Willebrand's disease (this is quite rare and unlikely).
Also, be sure to take a multivitamin and eat foods high in iron so that you don't become anemic!
Good luck!
Dr B
Thank you That helps alot :)