Been having some bleeding during taking a stool... someone tell me what to expect what this might be or the cause? been happening for a while now.

BLOOD WITH STOOLS: Blood with stools needs to be checked by your doctor.It may be due to Hemorroids,,straining due to hard stools,anal fissure,colon or rectal polyps,inflammatory Bowel Disease ,polyps in colon/rectum and in some cases colon cancer Cosult your doctor or a gastroenterologist.You need a thorough History and Physical Exam including rectal exam and may need colonoscopy if indicated

Bloody stool : This maybe caused by few different conditions .. At your age I highly suspect that hemorrhoids maybe the reason for them ... Some upper or lower gi bleeding meaning bleeding from the gi tract can cause this as well...

Get examined: most likely cause is hemorrhoids but must consult a doctor and get examined . usually blood is not mixed with stools if coming from hemorrhoids.