Septum healing period?

So, I’m thinking of getting my septum pierced, but my parents are definitely not okay with it (my mum has said she’ll tie a string to it and drag me through the house if I get it done), so I figure if I time it right- since I’m not living with them that I can take it out once it’s healed whenever I see them. Which brings me to my question- how long would it take to heal? I know there are the estimates that piercers tell you, but my experience is always WAY off from what they say.