Research suggests University students are more disposed than others to develop problematic social media use. Social media overload, the phenomenon where users are exposed to a massive amount of information and communication demands via social media that may require energy and cognitive processing beyond their capabilities, is the specific problem under investigation in this paper. Combining qualitative data with the situation–organism–behavior-consequence paradigm, we develop a research model of the etiology of social media overload and its consequences for student performance in higher education. Using SEM-PLS techniques to analyze survey data from 182 students revealed a fear of missing out (the situation) is associated with feelings of overload (the organism), which in turn is linked to deficient self-regulation (the behavior) and ultimately reduced performance (the consequence). Our study advances the understanding of problematic social media use among students by demonstrating the psychological and behavioral conditions which hinder academic performance. Interventions designed to address social media overload should target the performance antecedents identified in this study.