I have synesthesia too. Music or other sounds, certain chords and harmonies make me feel colors or shapes. Some songs make me see a kaleidoscope in my mind. Some letters and words have a color or feeling or shape. Days of the week and months are definitely different colors. I also associate people with colors or shapes. I must be extreme because I also associate places and things I've experienced with shapes or tastes or colors.

It's not at all bothersome, in fact, adds another dimension to life!