28 lbs at 11 months is very small. Is he short or skinny or both? My Lola is a tiny bulldog as her mom was only 35 lbs full grown and Lola weighs about 38 lbs now at 10 months old. There is no such thing as a mini bulldog as far as the breed goes, only "smaller than breed standard" bulldogs. He is a cutie though and if the vet says he is healthy and at a good weight for his height, you should consider yourself lucky. Some people would pay lots of money for a bully that small!