My right foot arch started hurting a little just after the ADRA run - they were past their due by date - and its been niggling a bit ever since. I had been doing quite a bit of walking on site for my job as well - not sure if that was a factor.
"Plantar fasciitis is a painful inflammatory condition of the foot caused by excessive wear to the plantar fascia that supports the arch or by biomechanical faults that cause abnormal pronation. The pain usually is felt on the underside of the heel, and is often most intense with the first steps of the day. It is commonly associated with long periods of weight bearing or sudden changes in weight bearing or activity. Obesity, weight gain, jobs that require a lot of walking on hard surfaces, shoes with little or no arch support, and inactivity are also associated with the condition."
This site has good info: http://www.marathontraining.com/articles/art_4th.html. It could also mean the problem is achilles tendinitis, a fat pad contusion (bruise on the bottom of your heel), plantar arch strain, tarsal tunnel syndrome.
A 5.5km yesterday on the flat felt a little pain at the start but faded after the first km - 5.51km, 24:38, 4:27min/km.
I think I need to give it a few days to rest - do some stretching exercises as well. When it's pain free I'll do another 5km see how it feels - and then gradually ease back with the distance.
Thinking about getting some swimming goggles today- no excuse now for cross training!