May be insect bite confirm once…wait for 2 t 3 days if doesn’t subside needs consultation…

Confirm whether it is due to any insect bite which might have occurred during trip, if not so apply some topical antiseptic cream and it will get healed within few days

Apply t bact cream over it

From the pictures, the small bony prominence just below the knee appears consistent with a normal anatomical structure of the upper tibia (tibial tuberosity or nearby bone contour), especially since there is no pain, swelling, redness, or difficulty walking. Such prominences often become noticeable incidentally due to positioning, lighting, weight changes, or muscle tension and are not necessarily new. Sudden serious bone problems are unlikely without pain or trauma. At present, no treatment or investigation is required. If you later develop pain, increase in size, redness, or difficulty in knee movement, then an X-ray and clinical examination would be advisable.

Leave it, it can be healed by itself