[Bigiron]

Lip swallowing can also indicate suppressed speech, where the person is preventing themself from speaking when perhaps they know they should. This can indicate lying or maybe disapproval.

Pursed lips are a classic sign of anger, including when it is suppressed. It is effectively holding the mouth shut to prevent the person saying what they feel like saying. This may also be an indication of lying or withholding the truth as the person stops themselves from telling the truth.