Thanks for the query.
The possibilities for your irregular periods
causing fluctuations in the hormonal
levels at hypothalamo-pitutary-ovarian axis leading to irregular periods.
-Polycystic ovary disease.
So you better go for treatment for PCOD along with reduction in weight.
This will help in regularization of the cycles.
Reectal bleeding could be due to anal fissure
or hemorrhoids. So better to get examined once and take treament for it.