Answer
Seek immediate medical attention for persistent chest pain, breathlessness or palpitations because these can indicate myocarditis or pericarditis.
Sources for this answer
- Comirnaty LP.8.1 30 microgram/dose dispersion for injection in pre-filled syringe — Current selected SmPCemc · Summary of Product Characteristics
- NHSNHS · NHS medicine guidance
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.