Ladies please help don't know what's wrong?

Okay soo my mum's sister is suffering really badly .. Her sides are paining really badly and her stomach is gone big .. Her menstrual cycle is irregular ,, so she gets it once in like 5/6 months .. she feels like there is a bloodcloth or something stuck inside of her tummy .. And only drops of blood comes out now so she thinks she has her period and also when she goes to the toilet it burns when she pee's . what could be wrong with her ? And if it is a blood cloth how can she take it out ,, Oh and her age is 45 and she had ligation after her 4th child which was like 16 years ago