The hard lump under the scar could be a HYPERTROPHIC SCAR/ KELOID. This appears when there is an injury
in the deep dermis(skin) and any injury heals with inflammation and scarring. There is a deposit of excess collagen
which results in the lumpy feel. Most hypertrophic scars
may undergo partial spontaneous resolution, but it might take a couple of months.
Is the scar /lesion red in colour , any associated itching, tenderness/pain, is the lump elevated above the scar ? I would say dont worry about it. Try using MEDERMA ADVANCED SCAR GEL once a day on the scar/lump and gently massage
the gel onto the area once a day for about 2 months. It might reduce by then.Do not use mederma on open wounds.
There are also other modalities of treating hypertrophic scar/ keloid. These include occlusive dressings, compression therapy, and intralesional corticosteroid injections. Try Mederma gel application, and if you find no improvement at all in 2 months, consult your doctor for info about other modalities of treatment.
Have a nice day :)