Why training more has dampen my spirit instead of uplifting it?

I have. i was forced to go to a mc dojo for about a year and dominated everyone there including the "Best" black belt students/ teachers and left the dojo. I returned to my old one and sparred and got destroyed. My skills diminished and i felt very down and even cried during the first week on my return. But i said to myself "No don't beat yourself up, work your way back up. Become better than you have ever been and train harder". A few weeks later i was back and even better and now, against legit black belts, i am a match. It was 2 years ago and i'm glad i went through that. I was over confident in my skills and i had to be shown i wasn't as good as I though. Now i'm one of the top students at my dojo. Of course i still get hit and stuff but dont give up. You will get better it's part of martial arts. We all hit a wall eventually you have to break it down.