Cursed child doe patronus

Just wondering here! I saw the cursed child play in Atlanta this week and it had some really great effects! BUT something has been nagging at me and I don’t know if it was just a malfunction, or done by design! The doe patronus appeared as only a head…..I feel like with the magnitude of the other effects this was….underwhelming! Is it a malfunction or is that how it’s supposed to be