Make sure to count during an active time of day, when you feel him being real active then start counting. My girl was especially lazy in the heat, but when it cooled in the evenings I would lie down on my left side, drink some water and usually she would kick more than 10 times in less than an hour lol if this doesn't work, call your doctor and ask what to do next.

Lay on your left side and drink some juice or eat some candy and then count how many kicks in an hour. He may be sleeping