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.
Everything about bitcoin is considered as risky. It just depends on you how you would take the risk. If it's an opportunity or not. Who knows maybe if you hold your bitcoin for a little bit longer, it may either increase or decrease its rate but the good thing is you can learn from your experiences.