Thank you for the query.
Fatigue and dizziness may be caused because of low hemoglobin level. Especially that you have significant rectal bleeding
. If you add to this symptoms severe constipations and abdominal pain
we can suspect that something wrong is happening in large intestine.
Such symptoms should not be neglected, and colonoscopy
should be performed as soon as possible as there is a rusk that you are suffering from colon cancer
. If you have also lost recently weight, it is very advisable to have this examination.
Other reasons of rectal bleeding are hemmrohoids or anal fissure
, but this conditions are often associated with anal pain.
Hope this will help.