THIS is what I'm afraid of

Here's something I want to share with someone, simply you're the guys I want to share this with. ok, here it goes.
:)
When I was 13, if someone asked me if I would ever go on a mission I would say "What? No! of course not!" (I know, is not very polite or fine, but anyways) Then, when I was 15 I started working on my personal progress. If someone asked me if I would ever go on a mission... then I said "I don't know, I still have plenty of time to decide".
There I was, my 18th Birthday. My Medallion and Honor bee on my neck. Someone asked. So, are you going to a mission so far? And my answer was: "It could be, It depends on what i'll be doing".
My 19th Birthday is coming REALLY fast, maybe faster than I thought and, a year later, I've been thinking about mission, missionaries, joy of serving, and that kind of things and suddenly I asked for a "preach my gospel" and "Teaching" Manuals.

I'm really considerating going on a mission, but the problem is, I'M TOTALLY SCARED. I don't know why, I've been praying a lot, I don't know what my parents -they want me to study and work- would say to this.
My testimony of the Church is growing every time I have the opportunity to study the gospel.
What do you say?