Having pcod and mid cycle bleeding.

I was having krimson 35 for a couple of months due to irregular bleeding. I stopped for a month as the doc advised to give a break and was having periods evry 15 days and not stopping completely. So I have started it back and 20 days with the medicine still having bleeding inside( dark brown clotted) and some spotting at times and pelvic cramp every night the kind of pain that happens during menses but not throughout the day. I exercise regularly and if I do heavy exercise sometimes I see the spotting. I was also under medication for anxiety (serta 25) and inderal 10 which I have recently stopped at will a couple of days back and since then I started having cramp. I'm really confused at what is causing the bleeding and why is it not going away. I also take normoz daily. Is there any interaction between stopping serta and this? I did USG a couple of months back and the doc said it's a very mild pcod.i also consume alcohol ( one bottle beer every two days) to take off work stress.