Advice & Opinions PLEASE :(

Hi ladies! I'm 15 years old and my 16th birthday is in a month! I've always wanted a septum piercing but lately I've been thinking about it a lot! I also really really want a medusa piercing because I think they look super nice together! The only problem is that in my state you need parental consent and my parents think they are ugly and will get infected, even though I know how to care for them and love the way they look. They would make me so happy. I'm not a bad kid-I get good grades, obey their rules and behave really well. How can I convince them? :-(