Shin Pain

Hi, I’ve been experiencing really bad shin pain starting on Tuesday. I ran a long run of 10 Miles Saturday, and then Tuesday started back up but I could barely run 3 miles from the pain in my shins. It almost feels like a bone pain but it could be shin splints I’m not sure. I did heel walks and stretches but today when I attempted to run the pain was still strong. I have my half marathon in 2 weeks and im nervous because of this pain. Any tips would be appreciated!!
Thanks