Hello P.
I'm sure everyone here is only trying to help but it may seem like they're having a go at you for being full of confidence.
But I would think twice about the timing, I know exactly how you feel, I knew exactly what I wanted to be from the age of 6 and all I wanted to do was finish school and go straight to the big airlines!!
I'm 21 and I'll be finishing a degree in Business Studies from Dublin City University in 2003. I'll work in the area for a year until i finish my PPL here and then go Full Time training.
Just give yourself a back up just for security if not piece of mind!
18 IS VERY VERY YOUNG. It will happen, keep BELIEVING!!
Regards,
John