rectum bleeding but no pain?

i've recently been bleeding after some bowel movements,the first time it happened i shook it off because it didn't happen again until about 2 weeks later i want to say? and now since then i've been bleeding a lot more times not every but a few times, theres no pain, i'm not constipated really i just don't know i've never experienced anything like this before? and the first time it happened later on the day when i went to use the restroom that day i seen i was still bleeding a little because my underwear were stained a little but i haven't stained anything since? i want to call my doctor but wanted to get some opinions on here as well