Pre-season Elo

I'm very curious what's up with the Elo system during pre-season. I've won 14 out of my last 20 games, and I keep getting placed into lower and lower mmr rated matches. Can someone explain to me what is going on?

I am only gaining 17 per win even though at one point I had won 5 in a row.. and the very first loss I got was for -23lp. I'm not sure what's happening.

Did riot ruin it with the new system? Are we getting a hard reset in Jan?