endometrial cast aka decidual cast!?!

so i haven had a period in 8 months ,

so when i started spotting on sunday i was happy thinking ya know maybe itll be back to normal a few days pass on valentines day morning i wake up in agonizing pain im talking wanting to fall to my knees pain anyways so my first instinc go to the bathroom right when i sit on the toilet i feel my uterus contracting and starting to push a min later i feel something come out something told me to check the toilet , when i looked i was instantly terrified what i saw was a skin colerd blob i had thought i had a miscarriage i was googiling pictures but it didnt look anythin like it so i started thinking maybe my uterus lining so i did some googling and sure enough it happens rarely mostly to eptopic pregnancy ( not preg) , what it is is when the full lining of the uterus falls off as a whole ! its cuased by many things but mine was caused by the depo shot i guess thats one of the rare side effects its so rare that an article i read the doctor of decades had only ever seen 2 throughout his whole career ! anyways someone tell me theyve experienced this before i have some questions like when does the cramping stop and ect.

pictures by google