This is just speculation, but it may be that the added fat (cream cheese) is slowing your digestion down a little, resulting in a slower rise and fall after meals.
Just out of interest, how low carb have you gone? Would you say you are ketogenic?
And how long have you been at those carb levels? The whole 4 months since diagnosis?
If your routine has remained the same (exercise has a significant impact) then other variables might be sleep and sleep deprivation, stress, maybe fighting off a virus...
Unfortunately, most docs just see bgs within the 'normal range' or 'pre-diabetic' which yours are, and lose interest. I suspect you would have to produce significantly diabetic figures before you started being taken seriously. Sad but true.