Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Use emergency services for breathing difficulty, seizures, fainting, inability to wake the child normally, severe bleeding, new weakness, or another immediate threat to the child's safety.
Routine follow-up appointments are not a substitute for emergency care.
Seek prompt medical advice for increasing pain, fever, wound redness, repeated vomiting, new limping, reduced use of a limb, worsening headaches, or important changes in behavior or alertness.
Follow-up should be tailored to the child's injuries and safety plan.
Routine medical visits may include checking wound or burn healing, fracture alignment, growth, movement, hearing, vision, and neurological function.
Repeat imaging or specialist appointments may be arranged when needed.
Mental health follow-up may continue even after physical injuries have healed.
Safe caregivers should tell clinicians about new symptoms or changes at home or school.
The article also says
The child's primary care clinician can monitor sleep, mood, behavior, school progress, and developmental milestones.
Every sign above is quoted from the sofidex article on Child physical abuse. If you are not sure, err upward — it is always reasonable to be checked.