With all the good news coming out in favor of bitcoin like
Expedia accepting bitcoin etc it's time to buy with the price going down. You will not be so lucky next week. I strongly believe it's going to reach $700 by end of next week!
The perfect time to buy bitcoin is the time when you know how to handle everything especially during its dump. It was a stupid decision when you buy without any knowledge in trading and investing and even with that coin you bought. Perfect time to buy is when it dump situation.