Although student mental health is known to be an issue and teacher mental health has garnered increasing attention, these two concerns are seldom considered in tandem despite their deep interconnection. New graduates entering classrooms for the first time face an inevitably steep learning curve as they become independent classroom practitioners, and for those who already experience anxiousness in their own learning, the associated challenges are likely to be intense. Alongside this, the recent increases in student mental health difficulties mean that these novice practitioners, already under stress, are placed in a position where they need to identify, refer, and support students showing signs of poor mental health, usually without any specific training or qualification. Drawing on two distinct yet complementary datasets—an online survey of preservice teachers and a survey with follow-up interviews of practising teachers—this paper examines intersecting challenges across different stages of teacher development. The findings reveal that practising early career teachers report low self-efficacy and high stress in managing student mental health, while preservice teachers experience elevated learning-related anxiety. Together, these insights signal a mounting crisis in the profession, which we argue indicates an urgent need for systemic reform and targeted professional development to better support and mental health preparedness to promote both student and staff wellbeing.