If you screw up an approach- never get established on the ILS for 20L and just parallel it and don't descend cause you have a glideslope nav flag and are trying to figure and what is wrong. Approach never tells you your off the LOC then turns you over to tower and they advise you that your parallel to the course you tell them you have a nav flag on both by then, tower asks if you have the field in sight which you just picked up so you don't start a missed they clear you for the visual for 20R since you almost lined up with it instead of 20 L . You land and are not questioned at all(not told to call the tower) but you know you screwed up HSI had the GPS not LOC. My questions are..... is this a violation ? If it is what is the process if they are going to look into to it? Is approach required to tell you prior to turning you over to tower that your are not established. They don't have simultaneous approachs and no traffic conflict was created. I am kicking myself for this but believe me i have learned a very good lesson. I appreciate any constructive info