I have constipation for 3 weeks on and off.pains when i go to bowel.last 2-3 days i saw 1/2 pellets of black balls along with normal poop.pl help?

First, clear it out: Each person with constipation needs to be sure there is no other disease causing it. If constipation is just due to slow movement of the food and poop through the gut, then the things to try are vegetables, water, prune juice, prunes, fiber+water, Miralax, (polyethylene glycol) senokot or other senna, milk of magnesia, other laxatives... A doctor can check for the CAUSE of constipation and prescribe helpful meds too.