If you can bring your plant upstairs and put it in a sunny window, one that gets 5+ hours of direct sun, you could solve a lot of your problems. If you can't you can't but it would be a big help.
A terra-cotta pot might not encourage mold in a top-watering scenario, but the plant in question is watered using the tray system. Both the soil and pot will become saturated with water, and the porous nature of the terra-cotta pot will ensure that it stays wet as hcarlton mentioned, and encourage mold growth.
That glass cover will increase humidity, but that's not going to help the plant. Once acclimated sundews will live in household humidity, the only thing it absolutely needs is the light change now. The extra humidity without good light will just make mold grow faster, and if you put the plant into any place with sun and you keep that on it will cook too.
Try moving the desk lamp closer to the plant (or vice versa). Desklamps generally have pretty low output, so I would keep the bulb very close to the plant (several inches away).
Is that glass container closed at the top? If it is a completely enclosed dome you risk roasting your plant when that window gets direct sunlight.
no its not
i just hope it gets better, because it looks pretty sad right now, how long does it take for a plant to spring back after a repot?
As Sash said, I would give it a few weeks to a month. As long as it has the proper conditions it will spring back quite vigorously. D. spatulata is a very durable species so I wouldn't worry about it.
I am also shocked by this sudden development. There might be something seriously wrong that nobody is considering.It's pretty surprising that the plant deteriorated that much in just three days. Was the plant already shrinking before you repotted it?