The term burnout is being used at increasing rates among physics students, particularly in the wake of the changes to instructional modality prompted by the COVID-19 pandemic. Combined with research linking burnout to negative health and career outcomes, this increase in burnout presents a concern with respect to students' performance and retention. In this research, we will examine the experiences of undergraduate physics students in order to understand how they experience burnout. At the beginning of Fall 2022, we conducted interviews with 7 undergraduates enrolled in upper-division physics or engineering physics classes at two large research universities. We analyzed the data to determine key symptoms that students who self-identified as having feelings of burnout experienced. Following the interview study, we conducted a survey of 24 students to further investigate the symptoms of students that experienced burnout in physics. This paper presents the symptoms of the students who self-identified as burned out and also discusses strategies used by students with lower levels of burnout.