Common signs include difficulty reading social cues and unspoken social rules, challenges with reciprocal conversation, significant distress around transitions or changes in routine, sensory sensitivities to sound, light, texture or touch, intense focused interests, and self-regulation challenges including emotional meltdowns that differ from typical tantrums. These signs are often subtle enough to be attributed to shyness, anxiety, or behavior problems — which is a major reason level 1 autism is frequently identified late.