How heavy is TOO heavy?

My period came 6 days early and it's the heaviest its ever been.
How heavy is too heavy? Is there a point I should be concerned? I use a diva cup, I'm on day 2 of my period and already I've completely filled up my diva cup 4 or 5 times (so basically 2.5-3oz of blood since the cup holds a little more than .5 oz). 
It just feels really excessive! 😷😷😷