This is easy.  Money.  I can't really afford to do this as an overseas student, but I wanted to do the course so bad that accepting the overseas status only choice I had, so I take step one hoping I can pay for the second step when the time comes.

Nothing else really worries me.  I understand there might be worries, workload; interaction; pressure; learning new skills etc. But I can manage those.  The nature of online study doesn't phase me, it is who I am in a sense. Only the financial aspect is out of my control so only this worries me.

But it will work out. These things always do.