After colonoscopy & medicine symptoms of infection got better but now having 1 symptom again during bowl movements-bleeding. is this signs of cancer?

Not necessarily : After having colonoscopy most likely you would know by now if you have a cancer or not! any bleeding should be investigated ! it could be as simple as hemorrhoid to more serious inflammatory or other conditions ! make sure to be checked 1st!

Bleeding nonspecific: While bleeding after or during a bowel movement can sometimes be a symptom of cancer in the bowels, it is unlikely. If you recently had a colonoscopy, the physician would have noted if there was any evidence of cancer. Bleeding can be a worrisome symptom and you should connect with your physician sooner rather than later to review your symptoms and discuss options for care.