That is very good present to your mother, I can imagine that she was very excited to see the result. On other hand I can understand you because it is very important person for you and you wanted to create something unique that will impress her and make her happy. The idea of different emotions is really great, that suggests that you really studied your mother and wanted to capture every single moment that you both lived together.
In many different cultures there is a comparison of human character with the animals and you incorporated it very well in your work. Would be good to know what was your mother's reaction to your drawing :)