Nobody knows the future. You can only say it is a bubble after it has burst. But as long as its up, its not a bubble. For years now bitcoin has shown long term growth consistently. Let the haters say its in a bubble, and let the few that are willing to invest out of their comfort zone, like those who still believe in bitcoin (count me in) reap the benifits..
So far its being the best which has provided the users huge earning potential on their investment
if made at correct times. Though I have read in couple of news paper and JPM CEO says its a fraud and bubble is about to burst. It seems to be incorrect for now as the price is in the range bound currently and hope it rises a smooth ride in future.
It doesn't matter when you invested. What matters is how long you held it for.
Even those who invested before the 2013 crash made money, if they were patient enough.