Penile burning after intercourse may be due to Candidal balanoposthitis
It is fungal infection
, caused by candida albicans.
There is possibility of candidal infection in your wife...., vulvovaginitis.
Take anti fungal tablets for few weeks.
Apply antifungal cream on affected area.
Give anti fungal tablets to your wife also.
Avoid sex for few weeks.
Have sitz bath in dettol
Improve immunity with immunobusters and nutritious food.
You will be alright, still ,you may consult dermatologist
I hope you got my answer.
Dr. Ilyas Patel MD