I repotted my epidendrum (I think that's the type), but I'm not sure if it'll help :(

[jaydlyn123]

Hi there everyone, my name is Julie. I received a beautiful orchid about a month and half ago, with bright purple blooms. I've never had one before, so I got online and researched. I kept it where the sun could be on it, but never make it too hot. I only watered it once a week, and not too much. I fed it some orchid food with the water, and even crushed up egg shells into powder and mixed it with the water. It began to look like a harvested corn stalk after about a month, and it looked as if whatever was causing that spread up the stems to the blooms. They began to wither and fall off layer by layer.
I recently repotted it in a bigger ceramic pot, used orchid bark mulch that I soaked in water mixed with the orchid food for about an hour. While that was soaking I took the orchids out of the old pot and let cool water run over the roots...I noticed that some of the roots seemed spongy so I removed them. I let them hang to drip dry for about 30 minutes, then repotted them with the drained bark and put it in the window. It's only been a few days, but I'm worried I was too late. How long should I wait before taking any other action? I love my orchid and don't want to accidentally kill it! Help help help, please. I've attached a picture of the withering blooms and a picture of the drying stems. Any ideas?