Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern. As per your complain and presentation of symptoms all the symptoms are indicative of allergic reaction and the new symptom that you are experiencing that is swollen tongue is also due to allergic reaction. You should consult an Allergic medicine specialist and get a blood investigation done for allergic testing so that the exact irritant causing allergic reaction can be ruled out. Once the exact cause of allergy is ruled out, preventing exposure to that allergen can prevent outbreak of allergy symptoms.. In case if still there is exposure to allergen and there is an allergy attack you can take Cetrizine or Diphenhydramine [benadryl] for relief. For congestion by the time you reach hospital decongestant nasal sprays, broncodialators like Salbutamol in inhalar can be taken. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora.