Hi, Stomach pain and coughing could be due to lower respiratory infection(acute bronchitis) or reflux esophagitis or severe gastritis etc. You must undergo routine blood count with electrolytes and ultrasound of abdomen with x- ray chest to rule out infective pathology of lung. Treatment is mainly depend on the cause. You might require antibiotics (amoxycillin with clavulate and antiprotozoals like metronidazole etc.) with antispasmodics, antihistamines and other symptomatic treatment. So,better you must see general physician for complete history along with thoroughly clinical examination. Thanks.