Thanks for your question on Healthcare Magic. I can understand your concern. By your history and description, possibility of irritant cough is more. And it can be due to all the things you have mentioned like cutting and working blackberry bushes, inhaling pollens etc. These things are highly irritant in nature. When they inhaled, they cause inflammation in the trachea (center of chest-sternal area). And this gives you tingle or tickel sensations at the top of sternum. So better to avoid such things or wear face mask while doing those activities. At present take combination of antihistamine and anti inflammatory drugs. Do warm water gargles 5-6 times a. Drink plenty of fluids orally and keep your self hydrated. Don t worry, you will be alright. Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.