Relax,  your worries may be unfounded.  Plz go to your dentist and take x-rays.  Teeth may have late exfoliation and late eruption by 6 months to a year. Hopefully all will be well.  God bless u.

Normally the lower front 2 teeth start to shake and fall around the age of six years. However it may vary from person to person. There is nothing to worry about. If you really want to do something I would suggest you take your son for an iopa or small x-ray or an opg. This would confirm if the permanent teeth are present or not and further advice could be taken from your dentist as to what can or should be done.