Apeirophobia
Apeirophobia ( ə-PEER-ə-FOH-BEE-ə; from Ancient Greek: ᾰ̓́πειρος, romanized: ápeiros, lit. 'infinite, boundless') is the specific phobia of infinity, eternity, endlessness, or the uncountable and is also known as the fear of infinity, the fear of eternity, or the fear of endlessness, causing discomfort and sometimes panic attacks from intrusive thoughts of the infinity. It normally starts in adolescence or earlier and it is currently not known how it normally develops over time.