Adolescence can be a stressful period in life. The period contains challenges associated with the transition from childhood to adulthood (body changes, changes in interpersonal relationships, and identity changes). The aim was to investigate experiences of stress among adolescents in addition to stress related to the COVID-19 pandemic. Focus group interviews (n = 8) were conducted with girls (n = 22) and boys (n = 19) aged 13–15 in southern Sweden. The transcribed interviews were analyzed with qualitative content analysis. Analysis of the collected material resulted in two categories with four sub-categories each of which highlights adolescents’ experiences of stress. The results show that adolescents’ have a variety of experiences of stress, i.e., what they mean are the sources of stress and how stress is manifested. The adolescents experienced how stress was manifested both physically and emotionally. This affected both their sleep and performance. The adolescents reflected on both positive and negative manifestations of stress.