anyone experiencing really weird lp gains?

i ended season gold 4 with silver 1-2 mmr , i went 6 wins 4 loses and got silver 4 13 lp rank and there is something really weird cause i won the first game and only won 20 lp at season start (like if i had already silver 4 tanked mmr) i lost the next for 16 lp and then i won the next +21, that looked okay, i lost the next one also for 16 lp and won again for 21 lp and then that'S where the bullshit happened, i won the 2 next games but in both of these i only won 19 lp!, i really find this bullshit, im 11 wins 7 loses and the game what to fucking keep me in silver 4, im almost losing interest in the game with this shit, im already tanked and i wanted to reach fucking diamond this season but it looks like a fucking undoable chore.

edit : 4 win streak, now winning 18 lp, imma shoot myself....