Wow. You actually drew this from memory? Its great. :)

Yes. but that doesn't mean it looks may look like her ;)

Whoa... great. Can't do anything near as well as this no matter how hard I try -- and this is a sketchy one! Any advice for an amatuer such as myself? If not, that's perfectly fine...

Sure, Simoneer.. The biggest advice I can give is - draw from life!
Sketch people all the time! Also, make sure to study anatomy. and also when drawing, you're always making 'comparisons' i.e. where is this nose compared to the top of the lip. How far is the right eye away from the bridge of the nose, and then to the other eye..
Those little 'comparisons' also apply to tonal values and colour!
But the best way to keep improving is to 'observe' and 'report' through your hand/eye. Through drawing all.the.time.
Over time, you will build up an internal inventory of memories and skills. But you never stop learning.. I'm still learning with every drawing/painting i do. cheers!

Whether it looks like her or not... she's beautiful. :)

Great drawing. I love monotone pictures and this is gorgeous.