Hi, and thanks for your medical question on eHealth forum!
Periods can delay or come early by 7-10 days without any cause. However, since it is your 8th day, the first thing to be ruled out is miscarriage. The only way to confirm is take blood HCG tests 48 hours apart, and if the HCG levels are falling then it is a miscarriage.
A prolonged bleeding of any kind from the vagina can be due to a sore or ulcer in vagina as you see in Herpes or otherwise, endometritis or infection of endometrium of uterus, cervicitis or infection of cervix, fibroids, vaginal infections, vaginal polyp, endometriosis and cancer of either cervix, uterus or ovary. It can also be due to a hormonal contraceptive of any kind or due to hormonal imbalance due to withdrawing it. Sometimes PCOS also presents with prolonged vaginal bleed.
You would need to get some investigations done including hormone analysis, PAP smear, ultrasound and maybe CT scan of pelvis. Since a confirmed diagnosis cannot be given on net please consult your gynecologist regarding this. Hope this helps. Take care!