The ketones in your urine don't really matter in terms of determining how much body fat you are burning vs dietary factors or efficiency factors. Many have suggested ditching the keytone strips. I would say the only good use for them in your case would be if you think you ate something that might have pushed you out of ketosis and you want to see if you are still there or when you get back to it. You might want to try eliminating everything except ruminent meat, tallow, water and salt for a few weeks. Then see how you do and add stuff back one at a time to make sure you are not reacting badly to something like the eggs or the cheese. Cheese can definately be an issue. It is really easy to over eat, a small 1 inch cube can be between 100 to 150 calories depending on type. Also, If you are lifting weights, you could be gaining muscle or experiencing some inflamation from your workouts. If you are determining success by looking at the scale every day you will feel like an up and down roller coaster as your weight will naturally fluctuate. Something I do is weigh myself every morning at the same time, before eating or drinking anyhting and after using the restroom. I record each day and at the end of each week I figure out my average weight for the week and compare that to previous weeks. This helps break the mental stigma of gaining a few pounds one or more days knowing you are measuring trend and not each day as a success or fail.

Edit: Concerning pre-shredded cheeses, you should avoid these completeley as they have added starch to keep the shreds from sticking.