I think that investing in everything is risky especially bitcoin. Dont take anyones advice about what will happen with the currency. Personally I believe we are just starting, just my own opinion and you shouldnt consider that as investment advice as well.
I think Never invest more than you are able to lose Bitcoin is a very risky investment and you should keep in that in mind at all times. especially the price Bitcoin is still going down this time.

Nothing should stop you from investing in Bitcoin in 2018. Remember; the higher the risk, the greater the returns. Bitcoin is down now but could rise again in the near future. I will advice buying now that the price is low so you can generate good returns when prices rise