Is the League system wonky right now?

I ended last season Gold 5 around 70 LP. I basically sat in Gold for a few months cause I played relatively badly (I've gotten a lot better now), however during this season's placements I placed in Silver 2 after going 5 wins 5 losses (which was quite a surprise because I thought I would be lower?), rose to gold after a few days. In Gold 5 I won more than I lost and got to promos but it's not like I did amazingly spectacular, but still I raised from Gold 5 to Gold 3. I don't think my MMR was that high last season, so is riot's system just kind of messed right now?