Cerelle pill and lower back pain

Great pill been on and off twice for a few years, no side effects bar really really really tender and sore and sensitive breasts. I have such bad health anxiety and honestly this had my questioning if I needed to go to the doctors because of the scary big C that’s how sore and tender my breasts have been, can’t even lie on them.

Got pregnant on it because I wasn’t taking it properly, since having my son and ensuring to take it regularly I have had no issues

I used this for 6 months hoping my body would adjust but had to stop. My periods became really irregular, and super heavy. The first month, I had 2 periods (both lasted around 10-12 days), second month I got one period, 3rd month I got nothing, and then months 4 - 6 I had 3 periods in 7 weeks, all lasting around 12 days and far heavier than my normal periods. I felt like I had backache most of those last couple of months as that's something that happens whenever I'm menstruating. I've tried other pills and never had side effects like this, so I've stopped these now and will go back to another type of pill.