My 3 yo was extremely constipated, i had to help pull stool out as it was stuck. it came out with a few smears of red blood. is this normal?

No, but....: ..It is very common. A large, hard stool can cause a tiny tear in the anus and hence the blood. But you need to ask his pediatrician about dietary changes or medications to get the constipation under control. Although, not generally a "dangerous" condition, constipation can cause a lot of pain as well as toileting "accidents" in kids.