Are you sure those were flax seeds? The flax seeds I'm familiar with are way smaller than a sunflower seed; more the size of a sesame seed.
Could they trigger cravings? Anything's possible, I suppose, but I don't believe I've ever seen a post that eating flax seeds had triggered carb cravings.
Ground flax seed is a very healthy addition once you begin climbing the carb ladder; high in fiber and omega-3 fatty acids. Just take care not to overheat them since doing so destroys the omega-3.