You may be suffering from Polycystic ovarian syndrome
where you can have irregular periods
followed by heavy bleeding. You can skip your periods for two -three months or more. Please get your ultrasound
done to rule out adenomyosis
as it is also a cause of heavy bleeding. Since you mentioned you are trying to conceive and had heavy bleeding lasting longer than usual and are having delayed bleeding a possibility of miscarriage
should be ruled. Had you done a Urine pregnancy test. In case of inability to conceive for 6 mnts in women above 35 yrs should consult a gynaecologist as fertility starts decreasing after 35.