First, great effort... I can tell you put some time in this... you asked for feedback, so I'll give my constructive criticism (meant to be helpful, not anything negative).
On the looks... I dunno... something just not quite-right, but I can't put my finger on it. The lips and the eyebrows seem a bit off... both too narrow maybe? The eyebrows kinda look like those girls who shave their eyebrows off and draw them back on with a pencil.
If I were to sum-up my first thought when looking at this version of Hitler... I'd say "baby face"... not sure how to correct it though. I know LHs are difficult to do, and this is not my forte'.
P.S.
I guess I'm not getting a cookie, cuz I have no idea who's face you used as a base... good job on that.