my daughter is 2.6 years old.she can talk but not with us. she can say alphabet from A TO Z. Numbers from 1 to 20.twinkle twinkle little star star,even she can identify fruits, anima, their sounds but doesn't follow my instructions doesn't even talk to me. most of the times getting irritated and scratches her father and my faces.she is now suffering from few worm problems. I am confused whether it is speech delay or autism??