During the outbreak of the COVID-19 pandemic, social networks become the preeminent medium for communication, social discussion, and entertainment. Social network users are regularly expressing their opinions about the impacts of the coronavirus pandemic. Therefore, social networks serve as a reliable source for studying the topics, emotions, and attitudes of users that are discussed during the pandemic. In this paper, we investigate the reactions and attitudes of people towards topics raised on social media platforms. We collected data of two large-scale COVID-19 datasets from Twitter and Instagram for six and three months, respectively. The paper analyzes the reaction of social network users on different aspects including sentiment analysis, topics detection, emotions, and geo-temporal characteristics of our dataset. We show that the dominant sentiment reactions on social media are neutral while the most discussed topics by social network users are about health issues. The paper examines the countries that attracted more posts and reactions from people, as well as the distribution of health-related topics discussed in the most mentioned countries. We shed light on the temporal shift of topics over countries. Our results show that posts from the top-mentioned countries influence and attract more reaction worldwide than posts from other parts of the world.