What Causes Vaginal Discharge With Stomach Cramps?

Hi im a bit worried have been having real bad stomache cramps some times to the point of making me feel really quite unwell also some discharge. I had a miscarriage a few months ago and my tummy has felt the same i dont feel healthy im having periods i finished bout 2 days ago and now im getting a pinkish discharge with stringy bits which i also have been getting alot of since i lost the baby what is wrong with me please thank u