There is no way for anyone, even a doctor, do diagnose you over the internet. There are so many different things that can cause bowel problems, including irritable bowel syndrome, Crohn's disease, hemmarhoids, infectious bowel disease (other than Crohn's), a low-grad viral infection that has lingered, and cancer. You would need to have several tests done to determine what this is.
My advice would be to make an appointment to see your doctor. Meanwhile, write down all your symptoms, when they started, what makes them worse/better, etc. That way you'll be prepared when you see the doctor.