Welcome to Healthcaremagic
Thanks for your query
As you have mentioned, this knot at the shin does not look like a blood clot. It may be simply a soft tissue
swelling which may resolve with time but if it hurts, your doctor may prescribe you some antiinflammatory for a short duration and if it does not work, or else if the swelling increases, one may go for a fine needle aspiration cytology. Continue stokinets.
You can discuss this further with your treating doctor.
Wish you Good Health