Needtoknow, if you are newly on an antidepressant and responded that quickly, it is very likely a reaction to the AD, and not your depression lifting. If it is a reaction to the med, the longer you stay on it, the more damage it can do to you.
It happened to me nearly 2 years ago, and I stuck it out for 3 weeks before I could see my pdoc. I developed hyperacusis at that time, which no meds have been able to fix. I am still in a mixed episode, and have no idea how long it will take to resolve, if ever.

It is worth getting in touch with your pdoc and giving him/her your feedback so you can address it ASAP.

Take Care. TS