3 y/o hasn’t pooped since Saturday

Br

HELP! My 3 y/o hasn’t pooped since Saturday. We’re on vacation and she doesn’t like pooping in public or anywhere but home. But now it’s to the point where she won’t eat or drink anything because her tummy hurts. She refuses to poop bc she says she is scared. She still wears diapers. I’ve tried juice and flax seeds. Help please!!