LP Gain and Loss

Hi everyone I have a serious question. While climbing the ladder recently i've encountered a strange amount of LP Gain. I went on a 9 game win streak to Diamond 5 last night playing twitch jungle. Today I played my first d5 game (this season) and won my 10th game in a row only gaining 18 LP. The following game I lost the game losing 16 LP. Is the Lp system really that bad in low diamond currently? At least its better then the time master tier first came out I believe in season 5 or 6 but still this is sad.