Questions about ranked and earning LP

I dont understand what happened but i am in silver 5 right now and for some reason i suddenly started earning only 16 points for a win and losing 21 for a loss... i dont get it? its awfully unfair. thats a 35% differential between points won and points lost... with that ratio id have to win more than 60% of my games to ever climb in points... I've always gotten a little more or equal to the points for winning a game as i would lose for a loss. anyone have this happen before and know why? its just so discouraging cause while i have been gaining points... its very very slowly. ive always heard the high elo streamers say you need to win more than 50% of your games to win, but for me its wayyy more than that with such a huge difference in points earned and lost...