As you are having pcod, irregular periods is very common, getting periods after 56 days usually might have heavy bleeding..as you have mentioned you seen some tissue during periods that might most probably be a miscarriage.Once you get aborted and tested after a week,it shows negative... firstly get an ultrasound ,to confirm there is no retained products...
Next Steps
consult a gynaecologist regarding your future pregnancy.Try conceiving as early as possible as your age is 30.
Health Tips
start doing aerobic exercise,yoga,stop eating fatty food,have more of veggies..if your BMI is more then 25,then you need to decrease it.