Breakthrough bleeding

I'm 9 weeks pp and went back on the pill three weeks ago. I've been on this specific pill before and it's been the only pill that I never had issues with. On other pills, whenever I had anxiety for any length of time, I would have breakthrough bleeding. Doctors never believed me about this but there was a definite correlation for years. Now I have PPD and I've been bleeding for three weeks straight on the pill. Does anyone else breakthrough when very anxious or am I the only one?