Blood and mucus in diarrhoea for 2 weeks?

well that is good that your test came back negative. If I were you I would defiantly be going back to my dr and letting him or her know that you are still experiencing these problems and that they need to do further testing. Don't let them tell you that you are so young to be experiencing any kind of major problems. Have them do all test they need to do to rule out what ever is going on with you, just don't pass bolos and mucus through your anal for nothing. Hope things get better for you soon.