Prednisone withdrawal time span?

I had my wisdom teeth out last Thursday, and took prednisone for five days as I was instructed to do. Yesterday was the first full day that I didn't take any, and as the day went on I started to feel ill- lightheaded, nauseous, headache. I still feel slightly the same today. How long should it normally take for these effects to taper off given that I've been taking the prednisone for such a short time?