I always have a bitter taste in my mouth when i am hungry or when i woke up from sleep. what is my problem?

GERD: You have gastroesophageal reflux disease (gerd) aka heartburn. Take zantac/pepcid or Prilosec for a couple weeks. Both are otc. If that helps, that's the answer. Then see your doctor for follow up. If its chronic, you'll need to follow up with a gastroenterologist initially and then every few years.

See a doctor : you may need to see a GI doctor. Dysgeusia can be caused by different reasons: infection ( e.g. Gum disease), some medications, hormones, and acid reflux can affect the taste buds. See your primary doctor first.

Dysgeusia: is a change in your sense of taste and a metallic taste due to a variety of causes; from anxiety to dental problems (failure of a dental crown), medications and treatments.