Back pain that used to come only with periods but has now continued a full week past the period, spreads to the lower abdomen and stops you sitting straight is not simple muscular pain any more. In a 35-year-old woman this pattern makes me think of a pelvic cause - endometriosis, an ovarian cyst, adenomyosis or a chronic pelvic infection - and low
vitamin D with weak core muscles makes it worse. Painkillers on repeat will only mask it.
Next Steps
Get a pelvic ultrasound, urine routine, CBC,
vitamin D and
calcium done, and book a Practo consult with me with the reports - if the scan is clean we will treat it as mechanical with a proper physio and calcium/vitamin D plan.