Hii , Welcome To HCM & Thanks For Asking Your Query Here from the medical history you provided & as u said u had heavy bleeding for 3 days there is no possibility for pregnancy u did not provide information about when u had intercourse and what is the actual date of ur cycle if you have missed ur normal period and u start experiencing this after 2 weeks of normal period date than this bleeding can also a result of ectopic pregnancy and in this case you must immediately contact ur Ob/Gyn dr there are many other causes which may cause this including -Polycystic ovary Syndrome (PCOS) -Overactive thyroid or hyperthyroidism -Thickening of or polyps on the uterine lining -Uterine fibroids But seriously it needs thorough medical check up and investigations to spot a confirm diagnosis i would strongly suggest you to see a Gynecologist to rule out any underlying medical condition I hope it help Thanks & Get well Soon