big thing to me is that base of the ear should be infront of the head. I see why you did that, it looks like if you followed those two lines all the way the ear would be at a really bad and obviously wrong angle.
If you look at our two pictures, our ears have a little bit of a rounded rhombus like effect.
View attachment 43235 It's a little more obvious in mine, because I drew my ears by making the straight lines in about the shape I wanted my ear to be, added the curves, and then modified it until I was happy with it.
For the inside of the ears, instead of that third line across, the conical shape of the ear is better done as two lines curving together. I wrecked the one in my avatar at some point, but oddly the rushed one I did for Christmas in July did it right despite having the ears at a wierd angle lol
View attachment 43236
Hope this helps :u