You'll know if you have a huge problem. A family house we rented out was so infested with them when the tenants moved out that when you walked in they started swarming up your legs. It was disgusting!!
It sounds like your little one just happened to get a few fleas and you nipped it in the bud. A bath with Dawn dish soap and washing his bedding should do the trick.
If you're extra paranoid you can have someone spray poison or you can buy household flea and tick sprays.