Starting to wonder if im not meant to be a runner?

Everytime I try to up my mileage something seems to go wrong.  Not sure if this is just sore muscles or arthitis or something worse yet.  Maybe with couple days rest my ankle will be ok.   I did run 8 miles on it saturday and ran one of my best times in a 5K race sunday, 24:40,   but it hurt.  Actually its not worse today then yesterday so I guess thats a good sign.  It is same ankle I broke long long time ago, had surgery, a pin was put in, and sprained it hundreds of times since. 

Now I also know I upped my mileage too fast.   I thought I was ready.  I expected some soreness but not this.  Well see what a few days rest does for it.  Im registered for a half marathon on sunday, feel 95% ready.  If it wasnt for ankle would be 100%.  Hoping im just down for nothing and just need a few days off.  I was overdo for a cutback week.    I could probably run it on this ankle, I ran 8 on it saturday.    Ok enough feeling sorry about it,  just seems everytime I up mileage something goes wrong.  I know some of its my own fault.  Hopefully worse case scenario I just wait to go for a marathon in the fall instead of May.