Well, there you have it, it's been about 6 days into my "diet" and today I failed.
You didn't fail. You had a set back. It's best not to get hung up over stuff like this because it will happen.
If you are interested in a good fitness Youtuber I suggest Fat Meets fire. Dude lost a bunch of weight, disappeared from a bit, and it turns out he gained it all back. But he is currently working on losing it all again.