In this study, we investigated the symptoms of physical and mental health associated with lifestyle changes due to a lockdown among the students of a university in Northern Italy, one of the most affected areas in Europe during the first wave of COVID-19. We examined the psychopathological variations in relation to mental health problems in a young population. The goal was to develop interventions to resolve these new psychosocial problems. From June to July 2020, students participated in an anonymous survey asking about habits and symptoms that emerged during the lockdown and the COVID-19 pandemic. Five health outcomes were assessed: digestive disorders; headaches; fear of COVID-19; panic and anxiety crises; and depression/sadness. The conditions and duration of the social isolation, lifestyle, SARS-CoV-2 infection in the household, financial situation, and productivity were considered in the analysis. A total of 3533 students completed the survey. The participants experienced headaches, depression and sadness, digestive disorders, a fear of COVID-19, and anxiety/panic crises. The duration of isolation was associated with an increased risk of digestive disorders, headaches, and COVID-19 fear. The female gender, medium–intense telephone usage, sleep quality, memory difficulties, and performance reduction were associated with an increased risk of the health outcomes. Future interventions should focus on promoting and implementing different habits with the support of health and university organizations.