LP bug

So, yesterday i was playing League and unfortunately i left in the Champion select not by purpose, so i lost some LP even i was on 0, but i came later back, after my punishment for leaving Champion select expired and played ranked and won, got +21 LP, but got actually 8 LP, but ok, that was for leaving Champion select. After that i played one more game and lost it and dropped to 0 LP, and went to sleep afterwards. Today i woke up and decided to play one game, and look what happened: https://postimg.org/image/y7kgd1vl3/ So, i am not sure what happened here, but i would like if anyone could explain it to me. I'm confused about this one.