On my QXC I became a bit unsure of my position, but instead of asking for a QDM I went straight to 121.5 and asked for a practice training fix, and quick as a flash they pin-pointed me to only a mile or two off track. . .. .In my humble inexperienced ppl non flying instructor opinion I'd pass you on your QXC if you'd demonstrated the ability to keep cool and ask for a QDM or training fix if unsure of position rather than panic and continue completely lost and end up going straight through a busy control zone.. .. .Good luck and don't give up!