You might not be conscious of it, but there's a good chance you are shallow breather. People who are depressed or anxious often have tight chests which makes it difficult to do full, easy breathing.

Here's an early morning routine that will really help. Lie on your bed on your back so that you head is hanging over the edge. Hold a small (5/10 lbs - 2.2/4.5 kgs) dumbbell in both hands. Extend your arms behind your head so that they are hanging down towards the floor. Take a dozen deep breaths. Try to expand your rib cage as much as possible. If you don't have a dumbbell, improvise with a another object.

Release the weight. Move fully on to the bed so yours head is supported. Take another dozen breaths. Repeat the whole routine three times.

Enjoy your breakfast.