Anak, I really think you should see your doctor soon, these changes are best checked in person, especially the breast pain at the nipple color changes. Hindi siya normal-normal to ignore, kahit on pills ka pa.
Yes, contraceptive pills can delay your period or change your cycle, at yung brown discharge at period-like pain ay possible side effects din, pero yung breast pain combined with lahat ng ito, that needs a proper check, not just a PT. A few of my mum friends had weird reactions sa pills din, iba-iba lang ang body, kaya talaga need ng doctor. If you can't get a same-day appointment, I'd still push to see someone this week. Huwag mag-DIY ng PT ulit muna, let the doctor guide you kung kailangan pa based sa what they find, okay? You've got this, but go get checked.