Contraceptive pill question!!?

Me and my boyfriend have been in a relationship for over a year, and a physical relationship for 10 months or so.

I've had the contraceptive implant but this had to be removed 6 months later after making me seriously ill. We just trusted condoms for a few months and I've been on the contraceptive patch. However, I don't feel it's the best contraception for me simply because I'm very active and the sweat seems to make it fall off.

I would like to go on the pill, but my mother is very anti against it! I'm 18 years old and still live at home. She thinks ill forget it and doesn't trust me to take it... What can I do to convince her to allow me to take this!?

Furthermore, I've got a doctors appointment on my own for the 15th April.