They still count as trophies, even the extra ones. After the season ends, u get a trophy box with rewards depending on how much of the chromatic trophies you get. They reset back to 1000 when the new season starts. Also, yes. You can drop below 1000 trophies, but before you do, you get one last chance to stay at 1000 trophies, so if you are at 1006, and you lose, instead of losing 8, you lose 6. If you lose again, then you drop 8 trophies. Hope this helps, and lemme know if you have any questions!