The only thing that makes people worry is price. But even that is on an upward trajectory. Look at all time highs. All time lows. What do their numbers tell you?
Nothing I'm afraid, because if they did before buying into the hype, they would have waited on the side for the price to fall down to enter.
In the same way, all the idiots calling themselves experts made the same mistake, so it's not that newbies are the only ones to blame for doing the wrong thing. Newbies, ok, that's pretty understandable if they burn themselves in the very beginning, because we have all been there at one point, but the very fact that people who know something about traditional markets and their cycles have done the same, is ridiculous, heck, retarded.
Fomo affects everyone, because the euphoria that flows through the market turns even the most conservative investors into yolo gamblers. No one wants to miss out. The feeling that you could have invested but didn't is killing, just like how some people right now think about how they could have sold last year but didn't.