period vaginal hemorrhaging?

Okay, so here's the deal... Ever since my 5th child was born 17 months ago, I've had issues with my periods, and for about 8 months I bled almost daily. A few months ago, everything went back to normal, and my periods came every 28 days like clockwork, lasted 7 days and the bleeding was normal. I started my period on Saturday, and all day everything was normal. That night, at 3 am, I put in a super tampon and went to bed. At 3:30 am, my 4 year old woke up wanting something to drink, so when I got up, I realized I was leaking (to the point that blood was running down my legs like I was peeing on myself). I got cleaned up, was a bit worried, but other than that one incident, Sunday (day 2) was completely normal. Day 3 I started bleeding a little heavier, changing tampons about every 2 hours, and in the evening (around 7 pm), I put in a fresh tampon to take a shower. 15 minutes later, when I stepped out of the shower, blood was again pouring down my legs. The rest of the evening was alright, still every two hours or so I had to change my pad and tampon (I started to double up with a super pad and super tampon on Sunday). Yesterday (day 4), the bleeding got heavy again, going back up to every 1 1/2 hours of needing to change, and today, day 5, I am changing my tampon and pad every single hour, though this last one was less than 30 minutes. I'm passing a lot of quarter and half dollar sized clots, the cramping is pretty mild, only had a couple of points where it was any worse than normal. I know this isn't a miscarriage, because I've had my tubes tied and do not have an active sex life at the moment... so my thought is that I am hemorrhaging for some reason, and yes, I know that I need to go to a doctor, but time wise it's not easy to do. I work 6 nights a week at a job that only has one other employee, and she cannot cover my shifts. I'm trying to figure out what I can do at home to ease this, if anything, and I am going to try to get to the E.R. tonight. Anyone know what could be causing this, or what doctors might do to fix it? During the 8 months of constant bleeding, they tried several birth control pills as well as the shot, and nothing stopped or even eased the bleeding, so I'm not sure if that will do anything this time around, either. But day 5 of my period, I'm usually switching to regular and light tampons, not bleeding through supers. I also have endometriosis (medically confirmed during one of my c-sections), so I've always been a moderately heavy bleeder and always had the cramping, but nothing that comes close to this. Any thoughts?