Very painful period after stopping estradiol, what to do?

[Ozma4]

Hi, so we are having donor egg treatment abroad and have recently had a hysteroscopy and biopsies taken to check things out. The consultant said he'd seen an area that corresponds with adenomyosis which will explain my very heavy long periods I've been having. After the procedure I have taken 5 days worth of estradiol tablets and cyclogest pessaries. I stopped those on Sunday so they could check on my bleed. That arrived yesterday but for the day before and still ongoing I have the most painful cramps I have ever had! It's a constant heavy aching pain and I just feel like curling in a ball. Also getting my lower back today too. Is this normal? Is it to do with the hormones I've been taking? Do I ride it out or what?? I feel like I should be able to manage this, it's only period pain, but because it's constant is beating me at the moment. Any advice would be appreciated...