NEED SERIOUS HELP!!

My 3 week old baby is extremely uncomfortable, fussy, and etc all because of constipation.. what can I give him/do to help him have a bowel movement??

I’ve tried prune juice with water, massaging his belly, and the bicycle movement with his legs. His pediatrician suggested the prune juice but that’s been a bust. I really don’t want my LO to suffer all weekend.

He’s strictly formula fed.