What do u think bitcoin will countinue this insane grow in 2018, its worth to hold my altcoins?
Bitcoin is the king of crypto's so that makes sense that it's growth will be continuous, what are the altcoins you are holding then? If those are the coins that has the potential then just hold it until it starts making it's pump.I am very disappointed, i started crypto 4 month ago, and my portfolio now worth the 1/3 value in bitcoin as when i started this..
Don't be disappointed, experience is the best teacher there is still a long run for the market of crypto's and what you need to do is just keep on working yourself base on what's happening. Studying about technical analysis and being familiar with the market.
2018 will be the year of altcoins, or bitcoin get an absolute dominance?
Bitcoin still. 
I started sys, bat, cfi, and other shitcoins already sold them with loss..
Now i learned, dont buy every shit that shilling in twitter
I did my own research, always buy in dip, and wont sell until have huge profit
I am holding now sub, rdn, phr, and small amount of bpl, but this btc rally is insane..