When i was a teenager I use to be addicted to flossing me teeth. Anytime I put something in my mouth I would floss. After a while I started to notice I was wearing away the gums between my teeth. The dentist told me I was also wearing away the enamel on my teeth. Only floss once a day and do not get too close to your gums.
Yes, espcially if you dont floss often and your gums are inflamed. Its important to floss twice daily to prevent gingevitis. When you dont and gingevitis sets in your gums become swollen and inflamed and will bleed when you floss or brush.
it can. if you floss too hard then your gums will start bleeding, but if you floss gently then it won't cut and bleed
try not to touch your gums with the floss only your teeth :)