Do hemorrhoids always bleed and become itchy? i had a colonoscopy that revealed hemorrhoids 3 yrs ago but now feel something at my anal opening

Depends: External hemorrhoids can itch, internal ones tend to be asymptomatic though both can bleed.

Not always: External hemorrhoids tend to cause painful itching while internal ones typically result in painless bleeding. Have your doc perform a rectal exam on you. He/she may recommend some otc creams/suppositories and even a repeat colonoscopy if the diagnosis is still unclear.