Congratulations!
In terms of increasing distance, my recommendation would be to start slow and focus on frequency. By focus on frequency, aim to consistently do 3 runs per week. If 5K is your current limit, consider doing something like this:
Week 1 - 3K (x2), 5k (x1)
Week 2 - 3K (x1), 5k (x2)
Week 3 - 5k (x2), 6.5K (x1)
Week 4 - 5k (x1), 6.5k (x2)
Week 5 - 6.5k (x3)
etc.
Continue with that pattern of small increases and see how your body does. It'll get you used to the frequency, so your body heals properly, and then the distance will come after that. Be sure to focus on stretching as you increase distance, invest in decent shoes and socks (blister socks are a god send) and try and enjoy the process!