Thank you for the query.
The blood in stool
should be verified at first. To do that upper GI endoscopy and colonoscopy
should be performed (upper GI should be done at first if the blood in stool is black or dark).
test should be repeated and you should visit gyneacologist for transvaginal ultrasound
Fool blood work should be performed (sometimes anemia can cause lack of period), urine test (blood in urine can be caused by urinary tract infection
or stones). Abdominal ultrasound should be performed as well.
Do not wait with this tests as blood in stool is a very serious symptom and should bot be neglected.
Hope this will help.