My fear is much more about  the decreasing the price of BTC and losing money.

Actually it is not a bubble. Since, when you look at the trend of BTC market price you can find out that it is trying to find more customers. When the customer rate is stable you will find a stable price for the BTC

This fast changing of bitcoin is directly linked to the market cap and the number of new people how join to the BTC. Wise people can use these fluctuations to have much more benefits.

I think it is a suitable time to buy bitcoin, it seems it goes up after Christmas holiday.

I think it is better to invest on new coins rather than bitcoin, since the trading with other coin may have a good rise. Bitcoin also can be profitable if you be wise and can trade at a suitable situation.

Never is too late, it is possible to invest now instead of postponing it. Since you think that it is too late.
If you can use fluctuation of this market you can even earn a significant amount of money. But think and study first, then find the best solution.

It seems people make it so expensive and it's not related just to one person