It was done by request of the commissioner. Pink is supposed to be "blissful" which they wanted me to draw for the last page. Blue is tired/relieved/sad. Yellow is indeed worried/scared like you said. Red would be angry, but she isn't angry in this comic!
ChocEnd
2020-01-17 16:00:00 +0000 UTC
So with the colour=mood matter in mind, would it be safe to assume the following?
Blue; Confused
Yellow; Worried/scared
Red; About to burst (wait, that's not an emotion. Seriously, outside of 'pained' I'm at a loss here.)