Girls, I don't know what to do. I had a miscarriage a year ago. My per...

Girls, I don't know what to do. I had a miscarriage a year ago. My period came nine months after giving birth, and they were like before pregnancy, it seemed like everything was recovering, but now there's a delay of 12 days. I went for an ultrasound, but it didn't show anything, she just said that the uterus is ready for menstruation, but somehow they aren't coming, and she said if they don't come within a few days, we'll do oxytocin injection to shrink the uterus. The period finally came yesterday, I took a blood test for hCG and today the result is less than 1.00. My stomach hurts like during periods, I go