Hi Shack,
Welcome to the Pain Management Forum.
It's my guess that your body is just adjusting to new activity. When you make new demands on muscles that have been inactive you can experience the sensations you describe.
The production of lactate and other metabolites during extreme exertion results in the burning sensation often felt in active muscles, though which exact metabolites are involved remains unclear.
You may want to slow down you activity regimen and go at a slower pack. If this continues or the pain increases be sure to consult your PCP. I hope you are soon feeling better and that you will be active in our community.
I'll look forward to your updates.
Take Care,
~Tuck
Stinging extremities are usually a sign of a pinched nerve(s). It could be your body just getting used to being used again though. I'd check with your GP's nurse and see what he/she thinks.