massive rating drop
There is a component of ratings that looks at how accurate your rating is. The theory is that when you are new or you haven't played for a long time, your rating may be less accurate.

That was your 5th blitz game, all against the same guy. When you lost, the statistics said that your previous game rating was very likely to be inaccurate on the high side and so it made a big adjustment.
When you play a few more games, those adjustments will go way down in size.