I also received radiation and chemo to treat my tonsil cancer. I lost my sweet taste bud during my treatment and even now, I cannot tell how sweet the food is. I won't expect any improvement since the situation has been like that for nearly 5 years. As for the other taste buds like salty, bitter and sour, I have never missed them and they are quite normal to me. If you have IMRT, the situation should be better, as what Gary said.
Be patient.
Karen