The symptoms you have are suggestive for hemorrhoids (swollen and inflamed veins around the anus or lower rectum).
They, usually, result from straining to move stool, chronic constipation or diarrhea, and anal intercourse (pressure on the walls of the rectum weakens the muscles that support the hemorrhoidal vessels, they then become enlarged and lose their support and result in a sac-like protrusion inside the rectal canal-called internal hemorrhoids).
Hemorrhoids that are inside the anus are known as internal hemorrhoids.
Their most common symptom is bright red blood covering the stool, on toilet paper, or in the toilet bowl.
An internal hemorrhoid may protrude through the anus outside the body, becoming irritated and painful. This is known as a protruding hemorrhoid.