Stress Fracture or Shin Splints

18M 5’4 140lbs Recently I ramped up my training intensity as a runner. I’ve always had some chronic shin pain, but assumed it was shin splints. Notably, I do have flat which I understand could play a role in how my lower legs absorb impact. Essentially, as of now my shins are tender to touch, but not at all walking or at rest, sometimes a little during running, but only if I really think about it. The pain is mostly diffuse, but I have about a 1 inch area ( maybe a little less ) on my shin that feels kind of sharp. Honestly, I’m a cheapskate so I don’t wanna go to the doctor unless this is truly something bad. Also, my right leg is more affected than my left, which also happens to be the side with a flatter arch.