Can one's blood sugar rise following a totally carb free meal (i.e. protein and fat only--bacon and eggs)? mine went up a little after bacon & eggs.

YES: The body produce sugar from its internal stores and that might cause a little rise Also the body utilises the fat and protein to get sugar through some biochemical processes; it is needed for the body to use for its normal function

Absolutely! How? New: glucose from (a) release of glycogen &/or (b) conversion protein & fat in liver (gluconeogenesis); part of being in ketosis; induced by glucagon output from the alpha cells of the pancreas (under brain control). This is how we prevent low glucose concentrations when fasting. However, when people become diabetic, they ↑ingly secrete glucose even while/after eating a meal, thus further ↑ing glucose.