General Causes of Pains/Injuries
In general, through my research and personal experience, I have found that injuries and pains are triggered by a sudden increase in training volume or intensity, incorrect form, incorrect foot strike, muscle imbalances, footwear that does not accommodate for your feet, or a combination of these factors.
Increase In Volume/Intensity
If you recently kicked up your training volume by more than 10% than the previous week, or you did a workout without proper base training and insufficient recovery, your issue could be an unexpected increase in volume/intensity that your body has not reacted to well
Incorrect Form/Foot Strike
Take a video of yourself doing strides and compare your form with a pro, see how they strike the ground, how they use their arms, how their feet/legs extend, etc. There are drills to work on form however this can take a while.
Improper footwear
Footwear is essential for a runner regardless of what distance they train for. Your feet and personal preferences are unique to you, and there are different shoes that accommodate for different factors. If you go to a running store and ask an employee to help you out, they will likely know what type of footwear is best for you and whether you would need any extra accommodations.