Did I overpot this dendrobium tobanese?

[Grim Tuesday]

One thing I've been struggling with as a new grower is figuring out how big of a pot to use (for my non-S/H plants), especially dendrobium and cattleya alliance plants. Three months after repotting this plant I read some descriptions of the plant where folks say it absolutely must not be overpotted. Is the pot I have it in too big? If so, is it worth moving back down to a smaller size, or would disturbing it do more damage? In general, what are some rules of thumb for choosing pot size?

The plant in question:
(Please ignore the tilt of the plant caused by it growing towards an off kilter light over the past two months )

https://i.postimg.cc/8P6JF2yX/PXL-20...-180129673.jpg