Hey Alan, I can't tell you if he is too small as I don't know anything about the breed, what I can tell you is that is one good looking dog Have fun
Give him time - he is still a puppy and will not be fully grown until he is 18 months/2 years old. Some dogs are slower growers than others, and some dogs are smaller than others of the same breed. Is there any reason for you to be concerned? If he is eating and drinking well and not losing weight, lively and active, I would not worry at this stage. What does your vet say?
He looks a strong puppy, all you can do is give him time. Glancing at the Malinois show rings when I pass, my impression is that, as a breed, they aren't quite as big as they used to be - I have no specialist knowledge though.
