What is the usual way to say something along the lines of "when I was young, petrol was cheap" or "when I was a kid, my family lived in Mexico".
You can say:
In these cases, you are talking about the time when you were a young man (note: not a kid nor a teenager). Perhaps you are now in your 40s/50s/60s etc, and you are talking about your 20s/30s.
You could also say:
In these cases, you are talking about the time when you were a kid or teenager.