craftgrrl | Problems with my machine, please help if you can!!

hey there everyone, I'm having real problems with my machine at the mo (a Toyota Jet Black) and wondered if anyone out here in Craftgrrl land could help me.

I just got my machine back from bein repaired for a diferent problem and all was well for a few hours. however, now the needle keeps hitting the needle plate. I've broken so many needles and am at my wits end. The needle is not aligned correctly anymore (it comes down at the front of the hole in the needle plate and hits every few stiches.) I have no idea how to remedy this, I really don't want to send it back again, I've been without it for too long already.

has anyone had this problem too?? is it something I can fix myself??

thanks in advance.x.x.x.x.x.x.x