Thanks for your question on Health Care Magic. I can understand your concern. Chest pain on breathing is commonly seen in pleurisy. And most common cause for pleurisy is lung infection. You are also having weakness and feverish feeling, so possibility of lung infection is more in your case. So better to get done chest x ray first. If chest x ray is normal then no need to worry for lung infection. Sometimes bronchitis can also cause similar symptoms. Bronchitis can be due to black mold exposure and pet exposure (you had both). So these kind of exposure can cause pleuritic type of chest pain on breathing but better to rule out lung infection first. Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.