First time under cyber attack

Fri Dec 8, I just finished deploying a image sharing website. And then I shared this happiness with a gif (13.8MB) uploaded on my website with mjj on Nodeseek.com. Then I noticed the network traffic became very huge, full of 1Gbps. At first, I did not think this is a big deal, maybe it was because a lot of friends on the internet were watching my gif, however, it became uncontrollable as I found my server was down. I realized that it must be done by some bad guys intentionally. It was a CC attack. When I logged into control panel and saw my server was out of memory. Shutdown or reboot button became useless. Lucky in misfortune, this attack did not last long, it was over that night. I can not imagine how bad a stranger can be on the internet. We have no grievances or animosity with each other, why did you attack me? Boring and stupid.