Everyone grieves in a different way, and I don't believe it isn't normal. As long as you aren't bottling it up, avoiding the sadness, or it is affecting your daily life (which it appears that it isn't) I wouldn't worry too much. Some people rarely cry but show their emotions and affections in a different way.

If it is worrying you however, I would suggest talking to a therapist who understands the processes of grief. They can help you work through the loss.