If you've really been watching Bitcoin market since 150$/BTC you should know that current happening are very similar to what happened in 2013 when BTC reached $1000 and then promptly crashed in value.
Just like you now people were declaring it dead, yet it rose back up and proceeded to reach its current all time high, Progress will never be linear, it will have spikes.
Although I must agree that at some point Bitcoin should stabilize and stop rising in value, I doubt that it will happen any time soon.
The crash was more sudden though wasn't it? The rise certainly was. I wasn't around then but from what I can see from charts it was pure market manipulation at play. Not enough people knew about bitcoins for them to be worth $1300 at that time. The market cap was just unsustainable. It's not the same this time, because we grew even further plus more people are into bitcoins plus there's a massive buy wall everywhere!