I bought a spider orchid and it had three spikes full of flowers. Once the flowers died, I waited for the the spikes to dry out and then I clipped them. I then repotted it with fine fir bark, perlite and charcole. I water it once a week and feed it every other week. It has three bulbs that are starting to shrivel. I don't know what I'm doing wrong. Am I over watering it... or should I feed it only once a month... Can I save it?
Brassias can have a bit of shrivelling of the bulbs and still be pretty OK. Fresh mix and it should come good. I have a number of Brassias and they grow on mounts where they aren't wet all the time. The bulbs are quite wrinkly but they are happy and growing and flowering on cue.
How likely it is to be 'save-able' depends on how poorly it is doing ... Many Oncidium alliance orchids (of which Brassia is one) can be very resilient! I wouldn't expect the current growth to return to looking healty, but it's possible that it can grow, and new growth can do well. It can take some time for a plant to rebound enough to bloom again, however.