You didn't infect the mother and she didn't pass HIV on to your son. Not every medical issue, like a common cough, is related to HIV. You did not have a risk for HIV.
As an adult, the only risks for HIV are:
1) having unprotected, penetrative vaginal or anal sex, or
2) sharing IV drug needles with other IV drug users.
Attempted penetration with your underwear on does not constitute a risk. If you do not do either of the two activities listed above, you will NEVER have to worry about HIV.