Interesting game! I included it in my compilation video series for the Clicker Jam Spring, if you’d like to check it out. :)

it wouldn't let me buy the upgrades for awhile even though I had enough, then it just let me buy them without taking any time from me. So I basically went from not being able to buy anything to winning instantly

I think improvement can be made to fit the theme, such as, time counter unit as years and in reverse, player could learn more detail of what happened from the cards. I like the concept and the colour scheme.

The third Time Period's card didn't show, and when I bought my first upgrade (Archeologist) the game unlocked all of the Time Periods to the caveman era (without unlocking any of the cards) and told me I had won.

I reset using the in-game option : The first tier upgrade (Historian if I remember?) can't be bought even with sufficient years.  Buying the Archeologist again gave me a "You Win!" message without showing any of the time period pop-ups like the first time around. 

You've got at least two pretty serious issues in the code - the first upgrade doesn't work, and the second (and last?) upgrade ends the game early.  

Average clicker with interesting story. The problem is with the clicking effect (because theres none at all)