Background: A preliminary study we conducted showed that software practitioners respond to requirements changes (RCs) with different emotions, and that their emotions vary at stages of the RC handling life cycle, such as receiving, developing, and delivering RCs. Objective: We wanted to study more comprehensively how practitioners emotionally respond to RCs. Method: We conducted a world-wide survey with the participation of 201 software practitioners. In our survey, we used the Job-related Affective Well-being Scale (JAWS) and open-ended questions to capture participants emotions when handling RCs in their work and query about the different circumstances when they feel these emotions. We used a combined approach of statistical analysis, JAWS, and Socio-Technical Grounded Theory (STGT) for Data Analysis to analyse our survey data. Findings: We identified (1) emotional responses to RCs, i.e., the most common emotions felt by practitioners when handling RCs; (2) different stimuli -such as the RC, the practitioner, team, manager, customer -that trigger these emotions through their own different characteristics; (3) emotion dynamics, i.e., the changes in emotions during the project and RC handling life cycles; (4) distinct events where particular emotions are triggered: project milestones, and RC stages; (5) and time related matters that regulate the emotion dynamics. Conclusion: Practitioners are not pleased with receiving RCs all the time. Last minute RCs introduced closer to a deadline especially violate emotional well-being of practitioners. We present some practical recommendations for practitioners to follow, including a dual-purpose emotion-centric decision guide to help decide when to introduce or accept an RC, and some future key research directions.