Disheartened, realise 'today' will turn into 'ages ago' (4,3)
I believe the answer is:
year dot
If this is the answer I cannot explain how the clue works.
Can you help me to learn more?
(Other definitions for year dot that I've seen before include "Ready to (anag.)" , "A very long time ago" , "Start of time (colloq.)" , "Since this is as long as anyone can remember" , "The beginning of time?" .)