dont worry about it, leave it another week,. Could easily be the yeast took more time to start up and get established.
only difference in using table sugar is the yeast need to break it into a more digestable form before consuming it, so it can take nominally longer to ferment
Im sure u dont but...Just dont pull the lid and hang your head over the beer tho as while u do all sorts of stuff falls off your head, (even if a slap ed like me) if you NEED to peek inside lift the lid a bit and peer in from the side..
Also take a gravity reading from a sample, a clean turkey baster is easy to sanitise to draw small samples when no tap is fitted to the fv.
if its just a slower ferment the gravity should be above or about the 1010 level.
the kit instructions should give you target OG and FG levels as a guideline.