Firstly, irregular bleeding is not caused by stool. You should get a hormonal
profile as well in addition to the sonogram to know the cause. The origin of the mass should be deciphered. You may take a second opinion
and also consult a surgeon should the mass be unrelated to the uterus
, tubes and ovaries. Most often, a tubo-ovarian mass may be misconceived as something else. Please get further advice from your doctor. Good luck.