Hay, 15 days is quite long na talaga, normally even heavy periods are around 5-7 days lang, so I'd suggest checking with your OB about this, lalo na na 3 months pa lang post-CS ikaw. A few of us moms had irregular bleeding months after delivery kaya hindi agad alarming, pero better safe than sorry with something na ganito na extended. How's your bleeding, is it heavy throughout, or nagiging lighter na towards the end? Either way, don't wait too long; your doctor needs to know kung nag-extend ganito ang regla mo after surgery.