You are describing a chest pain that has a pressure quality and it worsens with deep breaths. It also radiates to the abdomen. Chest pain is a concerning symptom because it can be a symptom of heart, lung, or stomach problems. A heart attack is unlikely in a young woman though I cannot absolutely rule it out since I do not know your medical history. That is why you should see your primary care doctor
soon. People with heart attacks usually have a left sided pressure chest pains that can radiate to the left jaw or arm. It is also associated with shortness of breath and nausea. You mention that you have pain when you take a deep breath. This is called pleuritic chest pain though it is usually a sharp pain, not a pressure pain. People with pleuritic chest pains should be ruled out for a pulmonary embolus and pneumothorax. A pulmonary embolus is a clot in the lung. People who are at risk are women who take birth control
(with estrogen), obese people, and immobile people. A pneumothorax is a tear in the lung. Both conditions can cause shortness of breath. Lastly, you could potentially have a gastrointestinal condition such as acid reflux disease, gastritis, or peptic ulcer
disease that could be causing your symptoms. You should see your primary care doctor as soon as possible. If you continue to have worsening symptoms and cannot see your primary care doctor, you can consider going to the emergency room.