Introduction: On 24th March 2020, a 21-day nationwide lockdown was announced by the prime minister of India. This was a beginning of more phases of lockdown. People had to stay indoors, with worries about an uncertain future, about the well-being of near and dear, the lockdown added to the stress of the pandemic. Aims and Objectives: Our study aims at finding out the responses of the residents of Chennai in the immediate aftermath of the initial 21day lockdown and to assess their mental health at that time. Materials and Methods: The study design was cross-sectional with a sample of 800. An online questionnaire was created using Google forms and was circulated via social media platforms. Post online consent, the participants filled up the questionnaire which included two psychiatric scales: ADNM-20 and HADS. IBM SPSS Software version 25 was used for analysing data. Results: Out of the total 800, 215(26.84%) participants had adjustment disorder, 109(13.6%) had anxiety and 50(6.24%) had depression. Significant mean difference was observed between males and females in the scores ADNM20 (t= 81.5, p= 0.0290), ANXIETY (t= 27.5, p=0.010), DEPRESSION (t= 25.9, p=0.039). For occupations, a significant group difference was on ANXIETY scale (F= 2.427, p= 0.047) and DEPRESSION scale (F= 3.994, p=0.003). A significant group difference was observed in adjustment (F= 2.973, p= 0.019) and anxiety (F= 2.786, P= 0.026) for time spent on watching corona news. Financial worries showed a significant association with adjustment (chi =28.128, p= 0.0001), anxiety (chi= 50.252, p=0.0001) and depression (chi = 16.661, p= 0.002). A significant association was found). A significant association was found between participants picking a fight with a family members and adjustment disorder (chi =64.328, p= 0.0001), anxiety (chi= 78.089, p= 0.0001) and depression (chi= 54.667, p= 0.0001). Conclusion: This study findings will prompt the policymakers, to intervene and prioritize mental health resources and substance use services, as these will be needed on a longer term. Domestic violence incidents that increased in Chennai during the lockdown have been highlighted in our study.