<human>: Ever since I started upping my mileage, I get pains that last for a day after a long run.

During the run, at some point between 5-10K I get mild feet pains that get worse and worse, and really hit the next day where it hurts to walk.

Initially it was mild, even when I ran 2 12K's on following days about a month ago. But ever since then its been getting worse and worse, the pain shows up earlier in the run, and it hurts more the day after.
Yesterday was completely weird, after about 5K it started hurting real bad and it made me slow down, and at about the 6.5K mark my feet fell asleep (you know, went numb) and I just kept running with the weirdest feeling ever.

I am slightly afraid of long term/bigger damage/injury, but what is really annoying me is how I was doing so good, making great progress with both upping the weekly mileage and pace, and now I just can't.

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<bot>: Pains from long runs, how do I find out what is causing it (form, shoes, anything else) and fix the problem