Period!

Ca
I'm currently 11weeks pp tomorrow. At 3 weeks pp i had the depo shot.. (i got pregnant with my first on the pill and it just doesn't work at all for me).
I bled after birth for the first two weeks then two weeks off and ever since i've not stop been bleeding. I'm not sure if it has something to do with the injection or that i'm still bleeding from birth because it's a mixture of old blood/new blood.
I have an appointment with the doctor tomorrow to discuss everything because i'm having really bad period pains on top of having to constantly go to the toilet.
Anyone have any ideas?