Baby is 16 weeks and constipated

FTM here.

I believe my baby is constipated. She’s 16w. She’ll tense up and belly will be hard. Hasn’t had a bowel movement since 2/18 (it’s been 2 days). What can I do to help her? Her pediatrician said at her 2 month shot appt not to worry until she hasn’t had a bowel movement in 5 days. But she’s super fussy, crying and didn’t sleep well at all throughout the might. She usually sleeps from 11-5 every night but she was up every hour last night. I’ve given her gas drops but is there something else I can do to help? I’ve heard people give some prune juice but wanted more advice.