Hello there! Yes! It is my original work and you won't have any copyright issues, since I copyrighted them to CC0! You can use them in any of your project, without the need to credit me! I would be honored thought, if you decided to credit :D! Enjoy!
Yes! You are right! You can check out the CC0 Copyright here: https://creativecommons.org/publicdomain/zero/1.0/deed.en