Morning after pill Ella

Cara
Ok so I missed the 7th pill on my birth control, I had sex that night and remember right after, so I took the emergency contraceptive pill Ella I had gotten with my year long script from planned parenthood. I got horrible cramping the next day and two days after taking it I started bleeding, HEAVY HEAVY BLEEDING. It's now been 5 days since I took it and I'm still bleeding and cramping like crazy. This honestly feels like a miscarriage at times. Is it normal to have this much pain and so much bleeding for days after? I've read that it will usually cause you period to be early by a few days but this is almost three weeks earlier than I expected.