Tang just scratches??

Hey after doing my weekly tank clean/water change i noticed my tang looks to have a couple scratches on his side. He doesnt like when im in the tank and does get a little frantic/aggresive so im thinking maybe he thrashed against a rock a bit? Or is this possibly the start of something else and they are acutally sores. Hope the picture is decent enough to see. Its the two white lines one above his pectoral fin and one to the side of his pectoral fin midway down his body.