Since I love using traditional screentones myself , I couldn't help but write a constructive critique for this piece.
However, let's start with the other areas first:

Anatomy: You are good, but there's room for improvement.
The hand appears too big on the picture, and it doesn't really look like it's holding the lollipop in a natural way.
The size of the hand is usually big enough to cover one half of the face (from chin to a bit above the eyebrow). Right now the hand looks like it could cover the whole face.

And if it was meant that the hand is supposed to be "closer to the camera", then it means you have made a classic composition failure. In order to make it look like it's placed closer the camera, you have to give more hints, like drawing a bit of the arm visible so we can see more clearly for example. Or using a foreshortening on the hand.

And when you hold smaller things in your hand, it often requires a "precision-grip". A precision-grip is when you grip something using only your fingertips - like a lollipop for example. You would hold it between your thumb and your index finger - with the other three as secondary support.
Now also remember that the thumb is placed a bit lower down on the hand. So it would look more natural if the lollipop was placed more between the thumb and the index finger, instead of being closest to the index as it is by now.

The easiest way to fix the hand would probably be to just shrink it a bit and move it a bit more to the right - which will automatically place the lollipop in a more natural position.

Besides than that, I think you've done a very good job on the rest of the hand, the knuckles are a tad small but that can vary depending on the artists own style.

Now to the composition:

I don't know what the main goal with your homework was, but I think the composition in this piece doesn't give off that much of a "freedom"-feeling.
The background with the birds is an exception - the diagonal flow is a really nice touch.

However, the rest of the picture - the portrait that is - does not make me think of freedom. (Sorry I guess I'm not your twin soul then)
What I think more of here is "Attitude", "Rebel" or "Punk". Just the hand gesture combined with what looks like iron bars as background works as symbols for "I may be in a cage, but I don't give a sh*t".

Another thing you should've considered was the placement of the portrait here, using the "Rules of 3rds" are recommended when it comes to simple composition. You will often hear to avoid placing important things in the middle area. The big white frame could be filled with the portrait instead, with the face placed a bit more to the left or right instead of center.

What you could do to improve the composition and also make it resemble the theme "freedom" better is pretty simple;

Think of the symbolism, iron bars are associated with a cage/prison. If you made the iron bars look more like someone had crushed them or damaged them (more than just using a texture that is) it would give more of an impression of "breaking free". If it's meant to be windows, pieces of broken glass work as well.

What more you could do to improve this even more is to make it look like the birds blend in to the picture, and by that I mean by adding black parts of the birds in the white frame, so it creates a negative-effect. This is, of course, just suggestions. You are free to do whatever you want with your art.

Now to the screentones:
I really like how you've used them here, the highlights on the lollipop is really neat. One thing that I can't avoid to notice is the tongue, I can see that you've stacked a second screentone above the base tone - but it has created a so called "Moire"-pattern. Which is something you should avoid, since it easily distracts the viewer.
Now, I know this can appear when you scan or view traditional screentones on a monitor. So if you know that you have stacked the tones in the right angle (and both tones having the same linecount) it might just only be a effect caused by the screen.

Summary:
It is a very cool and well done portrait. A few anatomical flaws, but overall very good.
On a compositional level I'd call this "beginner", since a portrait like this require more dynamics for the theme "freedom".
However, your style is very good. I still like the portrait, but it does not give me a feeling of freedom. I hope this critique is of any help.