If you didn't see a doctor before beginning your fitness program, schedule a check-up just to be safe; then follow your doctor's advice.
Be patient. Remember everyone progresses at their own pace; customize the plan your're using to your own fitness level. For example, repeat Week 3 if you don't feel ready to move on to Week 4, etc. Be sure you know the basics of how to stay properly hydrated, what proper pre- and post- run snacks/meal are, and when you should eat them. Check the weather, air quality and heat index where you live and plan accordingly.
Move at a pace that is just right for you. Listening to music makes a run less boring, but people have a tendency to adjust their pace to the beat of the music. Choose music that suits the pace you need to fit your fitness level. You can use web-based resources to get music customized to fit the pace/tempo you need.