Hello ma'am and welcome.
I am sorry to hear about your discomfort and long struggle. Yes, the breast enlargement and soreness could most probably be because of the pill. If the pill is causing such intolerable side effects, then I would advise you to report to your doctor and discontinue the same.
You can then request your doctor to check on your hormone levels and advise a pill accordingly which would best suit you and would also help to control and regularize your PCOS
Hope this helps.