Hi Renee,
I don't claim to be an expert, (4th yr) but I might be able to help you put things in perspective.
It's been 19 days since you installed the nucs,.I will assume the 5 frame nuclear had 2 frames of honey an/or pollen an 3 frames of brood in various stages.including lava,capped brood an emerging?With a laying Queen.Freshly capped happens about 7 days after egg is laid an should emerge as bee in 21 days. So new lava that you saw when you got the nuc. Could be hatching now- eggs laid that day could be emerging in the next few days.
The Queen needs to have room to lay eggs. I assume you added drawn 5 frames with cells suitable for laying. If she laid one side of a framework each day she has had enough time to fill 5 frames.if so she may be feeling crowded unless you added another 10 Fram box on top.
If you havent, you probably should now.
If you have queen cups with eggs, or a closed cell (like a peanut) they will probably swarm.
You might be able to delay swarm by #1 finding the queen.If you. have one you can kill / squish. All queen cups an cells. It's my understanding that will give you 10 days before you may have to do it again.Danger,if you don't have a queen an you kill the cells etc.- you will have killed the hive.
you can also pull frames with cells on them an start a new nuc.That's a little more advanced.
IF YOU HAVE FACEBOOK,I recently shared a segment about reading your frames which members seem to like.
Also, on youtube, Mike PALMER EXPLAINS ABOUT understanding swarms. Also,The Fat Beeman has one that is pretty good -same subject. Ie. preventing swarms.
Both of these gents provide insight to various situations an can be good resources.
Under Members only tab there is a list of mentors. Find one near you an call.St albans?.
hope this helps.
If More experienced beeks, can add or correct, I always appreciate comments.