I've had a heavy period for 4 weeks ...?

This is serious and could kill you--

It is a sign of some serious things, not the least of which is Ovarian Cancer.

Try a different doctor. Look for a woman.

I'm having the same problem with the very large blood clots size of a grapefruit. I see my doctor for the problem and she prescribe me Aygestin and after the first hour the bleeding stop , i was bleeding for days and use about 10 pads in hour that with me using 2 at a time, so now i'm suppose to get the Novasure Endometrial Abltion done , but since the doctor took my blood sugar test the pills is making my sugar level jump from the A1c 6.5 to 7.5 and now she doesnt want to do the treatment. May be you should look up the novasure treatment and ask your doctor about it. and by the way my iron level went down as well . Hope this help

Thats really not normal at all, and probably not good for you either. You might be losing too much blood and become anemic(not having enough iron). You definatly need to go back to the dr and find out whats wrong and probably go back on birth control. It sounds like a hormone problem.

When my were like that I had uterine fibroids. They had to do an ultrasound to tell for sure.

this happend to my mum once...

it should be fine, just go to your doctor again they should give you some sort of other pill to stop it