Well hello there Indie! Sounds like you got a lot on your mind. I dunno what HSC means but it sounds important! I've been in that position, thinking "what the hell am I gonna do now?". It's never usually as bad as you think it is and like you said, if you make a not so great decision you can change. Ni will guide you! Hopefully.
I'm just getting everything sorted for uni at the moment. Plus i'm going to see a certain ENFP (I think she is. I HOPE she is, I've ran with it so far so she better be!) girl on monday for coffee. The aftermath will either be severe depression or severe euphoria. Fantastic!