Hi karen ! Listen first you have to take care of your blood loss. It can give you thousands of symptoms of disease. You need stool examination for occult blood if bleed around stomach or in the middle of intestine. You can't take much pain killer as you already anemic. About amytryptaline . It's a sadative also use for depression
can't make any good to your knees. So just go for colonoscopy
and stool examination. Recover soon, be healthy. Bye.