The dominant leg is usually the same side as the preferred hand. Sometimes people do have mixed dominance. This means like you they use the hand on one side and the leg on the other side most often. There is also eye and ear dominance based on which side is preferred.

Some soccer coaches think being able to use either leg equally is better than being strongly dominant on one side of the other. Your coach may not know you already use either leg equally well. You may want to discuss this further before training one side more than the other.