Any ideas for odd foot injury

Am posting since my observation of this forum gives me more confidence than any physio/GP I've seen.

Have not really run for 8/9 days due to a cold, However, during this period I've seemingly picked up a foot injury I can't diagnose.

Symptoms

Sharp pain on outside of R heel when swinging the leg forward (ie just before heel strike).

No pain when standing or when applying pressure etc

can replicate easily by
1) bending leg at knee
2) Pointing toes upwards (contracting shin muscles
[no sensation at this point]
3) Straightening leg - about 2" above ground heel starts to receive sharp pain.

Don't know whether to ignore it, rest, stretch it or what

thanks for any ideas

..and this pain disappears when you strike the ground?.. in other words it comes on because of the raising of the toes/ dropping of the heal?..

yep, as soon as I roll forward onto teh ball of the foot - no pain.

In fact on the one short run I did I was initially running on my Right forefoot in a kind of 1 sided lollop. Untill I " grinned and bore it" and a the endorphins deadened the pain away and I was able to carry on.