Phalaenopsis new leaf changed color overnight

[Kingak]

Hello all,

One of my otherwise healthy looking Phalaenopsis’ newest leaf changed color in the middle overnight, I didn’t touch it at all and I’m not sure what may have caused it.. doesn’t look like mechanical damage, and the part that changed color lost its volume/thickness (if that makes sense?).

Does anyone know what may be the cause and if I should be worried?

Thank you so much in advance!