Hello. Thank you for asking at HCM. From your history, I think you are having a severe allergic rhinitis. I would suggest you to take intranasal corticosteroids and montelukast for 2 weeks. Once inflammation of your nasal mucous membranes is controlled, they will become less reactive to external triggers such as cold, dust, etc. In addition, I would also suggest daily nasal irrigation with saline spray 3 to 4 times a day. Please avoid exposure to dust, cold dry air, smoke, air-pollutants as much as possible. Please avoid cold food & cold drinks also. I assume you don t have breathing difficulty. There are many possible causes for feeling of fast heartbeats, including but not limited to, some drugs (including some antihistamines for rhinitis), anxiety, stress, etc. I would suggest you to consult a physician if the cause is not apparent. Hope this helps you. Wish you best of the health. Regards.