Well, it's perhaps a DDOS, did your internet get cut off for 5+ minutes after it came up? If not, it is someone hacking into SOMETHING in your conputer, which could mean pictures to memory etc. I would suggest a reboot, however it would take long, and lose everything.
@halothe23 would know WHUT
First, DDoS is not a malware, virus, flying pig, or trojan. DDoS is something that works at the networking level, DDoS affects the traffic that your computer is able to generate to the internet, not the files that your computer has. DDoS in no way affects your computers files, programs or other, the thing it affects is the connection to the internet, in case your own one got attacked.
Immagine DDoS as unplugging your router, or turning off the wifi, same thing. (Does turning off the wifi give you a virus? No. So, does getting DDoS'ed give you a virus? No.)
Also, not every pop-up on your computer means someone is trying to hack you, stop watching movies.
Quarantine is a specific feature in antiviruses, which basically takes the virus and stores it in a secure place where it can do no harm. Its meant to be there in case the virus affected other files which you do not want to immediately erase, or if the antivirus had a false alarm, and marked your cat picture collection as a virus, you kind of do not want it to be deleted straight away, so it goes into this magical secure chest, where its kept there, until you tell it to delete it. (Some AV products feature a time limit, where stuff older then a month in quarantine gets deleted automatically.)
For now, just run a full scan, if nothing pops up, then the antivirus did its job.