Investing in bitcoin is a risk, as the value can crash tomorrow.
I'm holding too so far, I believe in what bitcoin represents, so I'm taking the risk. Don't invest more than what you can afford to lose however, but if you can, you should buy more.
Also have a look in other cryptocurrencies.
agree with you,bitcoin invest risky. no one tell you what happen tomorrow. but if you don't take risk you can't gain smoothly. risk is the part of life,so take risk & enjoy profit.
best of luck