Hi there!
Well, without a detailed clinical evaluation it would be difficult to determine the cause of your symptoms. Possibilities that may need to be considered include GU infections, inflammations, hormonal causes, growths/ masses, injuries/ trauma, ulcers/ erosions, haematological causes etc. Bleeding for more than 7-10 days would require an evaluation by a gynaecologist to look for secondary issues and depending on the cause diagnosed, it can be managed accordingly. Also if the bleeding is severe or one experiences additional symptoms such as dizziness etc., a visit to the ER would be suggested.
Hope this is helpful.
Take care!