Foot is puffy near the malleolus, no pain except if i push the area near the tendon which is quite brim but has a normal color. no trauma.

Tendinitis perhaps: always hard to tell without actually examining it, but a overuse type of tendinitis can occur due to repetitive motion or sudden increase in intensity of a motion in a body part not used to it. General trwatment is ice 15-20 min 3 times a day and NSAIDs. Decrease your amount or intensity of activity, and if not improving after a few days to a week, see your doctor.