5 week old super constipated...

my 5 week old daughter keeps getting really constipated an nothing seems to be helping her I tried prune juice apple juice tried putting Vaseline in her bum an nothing seems to be helping her get it out it has been over 24 hours since she last went and now this morning she has been crying non stop as I think she is in pain. Anyone have any ideas as to how to help her before I call her doctor?