How do I get my regular voice back?

Time, relaxation, voice lessons.

I found this site for how to warm up and take care of your vocal cords for singers. They give good advise whether you are a singer or not. If you don’t like drinking warm tea (add honey if you do) than gently gargle with warm salt water. Its good for soothing your throat and repairing damage to the throat.

Try gargling with honey and lemon to get your vocal cords back to normal.

As a singer, I find that if I have a cold or sore throat, it takes about three weeks for my voice to get completely back to normal.

The alteration of your voice dues to an edema of the vocal cords caused by the infection. It will dissapear by itself and everything you do to accelerate it may make it worse.