It seems you have severe bronchitis,. Take acetaminophen with anti allergic and decongestant combination, Steam inhalation,warm saline gargle, broncho dilator like salbutamol or salmeterol puffs if not available may be oral and( I do not know which part of world you belong to but your area is bacterial infection prone you must start with a broad spectrum anti biotic) As such you are diabetic though under control you are more prone to infections which may have serious complications.See your doctor as soon as possible to avoid complications. Good Luck.