constipated 1yr old

Help!! My 13mo is so constipated right now. He kind of has been for a few days his stools have been hard to pass for him and comes out hard. But tonight has hasn’t been able to go and is crying in pain from trying. He already drinks a lot of water, I tried giving him prune juice, I gave him mommy bliss(I believe that’s the brand) for constipation, massaging his tummy. And nothing has worked. He just woke up in the middle of the night trying to go and he still can’t and he was crying so bad from the pain. He fell back asleep already. But I feel so bad and don’t know how to help him