Thank you very much for the useful information Jaime.
Okay this can be either due to fluid build up in the legs/feet or due to a clot in the veins of the leg.
You should see a doctor immediately to rule out this serious possibility of blood clots in the leg.
A doppler scan of the lower limbs will diagnose this with certainty.
So have this examined ASAP preferably at ER; and ruling out any thing serious will put your mind at ease.
If the doctor find a clot, he will start you on blood thinner medications which will minimize the chances of any complications.
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