to clot off means that the blood IN the hemmorhoid is clotted. it will form a bubble, and the circulation that used to exist in and out of it, will be clotted off. Its PAINFUL! after a few days the pain will either drive you to beg someone to fix it, or it will break open and you will see clotted blood in the bowl after a bowel movement. it can leak and drain for several days after a rupture on its on. its RARE to bleed to death from something like that, unless you are on blood thinners, and so forth. it tends to be self limiting.
I do hope you are feeling tons better this afternoon.
btw, sitting puts TONS of pressure on your backside. Either stand up or lay down. Try to avoid sitting till this heals.