If you are ill (in real life), the mug is a message that you will get better soon and enjoy newfound vitality.
A mug falling to the floor and breaking: illness or bad luck. Receiving a mug as a gift: an inheritance or an honorary post.
Depth Psychology: A mug in a dream always stands for good health and luck; it is a symbol, if in good condition, for the “chalice of life.” See Chalice, Cup, Goblet. [1]
A mug is usually associated with a warm beverage, which has connotations of comfort.
A mug in your dreams may be expressing a desire to feel nurtured. Many people might associate a mug with drinking coffee, and in this way this image could relate to the need for stimulation. [2]