It's a runner thing.

I would suggest running at least three days a week with a day of rest in between (basically run every other day). Start out running for about 10 minutes without worrying about speed/pace, then walking 10 minutes. Do this for about a week or two. Once you can do that try running 10 minutes, walking 10, then running 10 minutes again. Do this until you can get the hang of your running. Eventually your goal will be to eliminate the walking portion and move on to running for 20 minutes. Remember not to start off too fast otherwise you’ll tire out too quick. Your goal should be to focus on creating a “base” so-to-speak and build up your body’s endurance. Once you can run 20+ minutes without walking you can start working on speed. Hope this helps!