I think I made a mistake buying at $23,500 (obviously), so when should I really start to panic now that we dropped to $18K?
Wait , How could you call this as Mistake? answer this question first " What is your Plan for Investing"? are you term or daily base trading? because this will distinguish what will you act in the coming days.
At what price point now should I consider to add more to average in at? Like, if you owned a bitcoin at $23,500, would you wait for $10K or 15K to start adding more to average in your high price of $23,500?
you should have add when the price reached 17k because that seems to be the lowest price of this year.