There could be some variables worth investigating here:
- Which vegetables with the eggs? Did you check the ingredients and portion size on the sausage? I will freely admit that I've sandbagged myself not checking just what was in what I was eating.
- Whenever I see very different BG numbers, I always want to verify them. If the number is not what I expect, I take another test right then. Blood is not homogeneous and there are various things (cleanliness of the site, amount of blood drawn, storage of the test strips, built-in variation within the meter, etc.) that can affect the reading, so I don't live by the exact numbers I get (fortunately, as a T2 I don't have to). But in the case of both your 156 and your 88, unless I knew I typically ran in the 150s two hours after a low-carb meal or around 90 four hours after, I would have rechecked.
- Fat has no carbohydrates or glucose in it so unless there are additional ingredients with it, it should not raise your BG. Protein also has no carbs in its pure state. However in some diabetics the body can store larger amounts of proteins in the liverr and release them as glucose even days later. That usually is a function of demand/activity, but depending on what you were doing after your meal, it's a possibility that you saw some artifacts of that.