I dont know if I am to sympathize with you or not, how could you listen to peoples opinion without a strong conviction, you could have as well just carried your analysis and study to confirm if his prediction is right or not, now that we are already heading to $6000, you better still buy it now, and keep.
If you wanted to trade, you would have just split the money into 2, half for longer term investment and the remaining half for trading, but anyway, you still go the chance, because from $6000, we might really be heading towards $10,000 soon, so I dont expect any price reversal again for now till further notice.
How could you listen to someone's opinions if you have seen the market making it to a bullish trend? So sorry for that but i think there's no chances for regretting because there are still great opportunities ahead. Just keep holding some of your coins and do not let other people control your mind. We can gain huge profits as the price reaches another peak.
You know that many of us work with intuition a lot, I almost made that same mistake too if not for the intervention of technical analyses, it was from their that I studied the price movement for my trade and the moment it gave a green signal, I had to hold back, and I am glad I did not follow my emotion.
The difference between mine and his is that I have money that I have already invested in BTC during the bear market and that one has been tied to BTC ATH and till I see Bitcoin ATH before I can consider touching that, so I have a spare money that I can throw round the market for short term trade, and if one is to be successful in that, our analysis tools are what should matter most and not just opinions.