No, it is not possible that you got it through the original files FGunZ. If it did get triggered after you tried to launch FGunZ then the FGunZ files were not original and modified by malware. This is caused by either something you downloaded & installed or outdated software on your PC that has been exploited.
Go to https://geeksadvice.com/remove-jdyi-ransomware-virus/ for information on removal and decryption.
If you have no important information on your PC then I'd just completely re-install Windows.
