Alex's slow growth

by Abhishek
(India)

Hi! My dog's name is Alex.

Now his age is 4 months and 3 weeks approximately. His weight is about 15-16 kg nd height is 18 inches.

The main problem in him is his tail, which was cutted a little bit from the bottem when he was 1 month old accidentally and now the length of tail is not increasing.

The second concern is that he bites too much. My question is are his weight and height correct according to his age?

And the second question, is there any treatment for the proper growth of his tail?