To dream of an empty drinking glass represents confident expectations about something you are planning on doing. Expectations to do something easily. You know you can do something if you want to. Waiting for or needing one thing to happen before to you can do something easily.
To dream of drinking from a glass represents an easy or quick experience. A situation where you "taking it all in." Negatively, it may reflect a problem situation that you are getting involved with something too quickly. Something is happening faster than you want it to.
Consider what fluid you are drinking for additional meaning. For example, drinking milk from a glass may reflect a quick or easy experience that you feel is good for you or in your best interests.
Example: A woman dreamed of looking into an empty glass and then getting scared. In waking life she was considering killing herself, but then scared herself away from it.