I am the *worst* with plants.. but we bought a bromeliad for our Montessori preschool room and have been trying very hard to actually take care of it. It was beautiful and healthy for a good six months.

It started throwing pups and the flower started wilting, so I cut it off.. and then everything went to pieces. Now the bottoms of all the leaves are turning brown around the edges (even the pups are browning on the outside) and I don't know if it has been too dry or if it is experience crown rot?
I don't even know what type of bromeliad it is for sure.

For watering, we have been using a spray bottle to give it a good misting whenever it is dry, and watering the soil less than once a week (only when it is completely dry). I did put a little tap water in the tank a couple of times (I know it should have been distilled) but I don't think it sat in there for too long.
We tried moving it to the window for more light, but that placed it under the heating vent so we moved it away again.

It was in the 6 inch pot that I received it in from the grocery store florist, so the other day I repotted it into an 8 inch pot with a special well-draining bromeliad potting mix purchased from repotme, and when I took it out of the old pot the roots appeared to be filling the entire pot. But I am worried that repotting it won't help at this point. Is it dying?