I bought some bitcoin in March 2017, sell half of it in Dec 2017 and hodl the other half since then. The current downward trend seem to last for a very long time and I'm quite upset about it. What do you guys think? Should I hodl or sell all my BTC now?
Yes you should continue to hold your bitcoins because the market prices right now is currently low and in order to earn more profit then you should be waiting for the price to grow.