My rating at 10min is 1650 but I started to play 5min games and I dropped to 1400
You only joined a week ago so your rating has been adjusting rapidly and your "1650" rating was never actually higher than 1586.
Your blitz rating had fallen to 1482 before you switched to 5 minute chess, so mark the actual drop from there.
You are now at 1360, a little more than a 100 point drop.
100 point drops happen every day to people who play a lot and are not conclusive.
this is a new account
my other one is 1650 and I only play 10 min games there. I also have played more than 2000 games, so the rate is stabilized
I created this one to play 5 min games and I find 1300 players stronger than a 1550 at 10min
My rating at 10min is 1650 but I started to play 5min games and I dropped to 1400
You only joined a week ago so your rating has been adjusting rapidly and your "1650" rating was never actually higher than 1586.
Your blitz rating had fallen to 1482 before you switched to 5 minute chess, so mark the actual drop from there.
You are now at 1362, a little more than a 100 point drop.
100 point drops happen every day to people who play a lot and are not conclusive.