I've been going through this for around two years now. Will often go months without a period and then when I finally get one it can last 6 weeks.
I've been to the doctors and they said it's possible PCOS however I wasn't aware PCOS could cause such long menstruation and they haven't said for sure that is what's causing this. I've had an external ultrasound which showed nothing and blood tests, apparently my hormone levels are high. Still going to the doctors just waiting on more bloods to compare to the ones I had last time.
I was just wondering if anyone else had experiences this because people look horrified when I say I can have a period for 6 weeks. It's really worrying me.