From what you have specified it appears you have just had an abortion.
The pink spotting you observed earlier is normal when pregnant and occurs initially. But, your recent symptoms
of stomach cramping indicated you just had an abortion. It's very important; you do not do any strenuous work especially that that would increase your intra abdominal pressure. As pressure increase will compress on amniotic sac forming yet.
I suggest you consult a gynecologist to make sure that aborts ahs completely come out. As if there are remains of aborts, it would irritate the vessels causing excessive bleeding per vaginally. You should also know this does not mean you cannot conceive again. You definitely can, but make sure you take adequate care when pregnant. There are many help groups for ANC care. You can take help from them, who will explain all that needs to be taken care of when pregnant.