placements

You can't see your mmr (op.gg and similar estimates are often particularly wrong aorund the time of the soft reset). Odds are your mmr from last season combined with the soft reset resulted in a rather low mmr, hence the b5 placement.

Still, if you actually do have b1 mmr, you'll be getting like 35+ lp per win and will likely skip a division or two, so you'll get where you belong pretty quick.