I am showing a sensitivity to lactose, but not to milks or cheeses?

We test lactose at 100% the volume. Milk from animals contains varying amounts of lactose between 2 - 10%. Cheeses are known to contain between 0.5 - 2% lactose. Heavy cream is known to contain 0.02% - 2% lactose. 

As such, you may be intolerant to lactose if consumed over the 100% tolerance threshold but not be intolerant to different dairy products due to the lower amount of lactose they contain. 

However, it is essential to be mindful that if you are showing a sensitivity to lactose, then it is preferable to consume lower amounts of dairy to avoid taking you over your "intolerance threshold."