Do you have type 1 or type 2 diabetes? I have type 1, and I've found that house cleaning often lowers blood sugar to a point where I'm likely to go into a hypo. If you're taking a fast-taking insulin before dinner, lower the dose and test 1-2 hours after beginning dinner. The blood-sugar readings should be about 10 mmol/L (180 mg/dL). If it's significantly lower -- say 8 mmol or lesse -- this means you're shooting too much insulin before dinner. I imagine the same would hold if you have type 2 and taking an oral medication, but I have no experience with this.