the more you fiddle and lift the lid the more time it will take to cook as it's only just getting going now if it's set on high it will be ready by 6-ish if not before slow cookers do not need to be filled to the brim with liquid as they require v little stock i promise you that come dinner time you will have a deliciously moist chicken now off you go and make yourself a brew and leave it to work its'wonders
Be brave! I was very sceptical too when I first had one, but they are brilliant. As an aside, I often do poached chicken for the hounds in it, and the poaching liquid is a popular addition to their kibble. Also find that left over cooking juices from, say, a beef brisket (which is gorgeous in the slow cooker) would be very popular with any passing whippets you might happen to know.