IUD removal (mirena)

Hi, I got my iud removed after 5 years a little over a month ago. I had bleeding on/off for a little over a week following removal. Anyway I started bleeding 2 days ago (presumed it to be my period starting, 1st proper one post removal). It has been absolutely horrendous. I have bled through a tampon + pad in an hour for the whole time. Feeling super dizzy. Last night bleeding crazy and passing clots and sitting on the toilet having full on contraction like pains on and off for a good while. Has anyone ever experienced this. Is this normal for first period after? Was it a period? Any advice appreciated!