Yes, the queen does have the capacity to stop laying... it depends on a number of factors but more often that not it's flow related i.e. whether there is sufficient pollen and nectar to support brood development... when i was starting out you wouldn't believe the amount of times I looked in my hives and freaked out thinking my hive was queenless because i couldn't see any eggs - sometimes it's as simple as giving them a bit of a feed to get her going again (obviously dependent on what time of year etc it is). In my case though i kinda ran before i could walk - wen't from a newbie with one hive to almost 20 in one year! 50 in my second year so i've had to learn pretty quickly! it's been an awesome experience though!