I feel like we all need @Shadrach to stay up all night watching the broody cam and giving advice live. Sort of emergency tele-medicine for chickens. It would certainly calm me down!Sounds like peeping to me Bob.
You may have chicks in the morning. That's when I tend to find them.
Be aware that if she does hatch and the chicks get to the front of the nest, she may well peck at them. New mums get very anxious when the chicks are at the front. They know the chicks should be at the back usually in with the eggs. In straw nests quite often the chick can't get back underneath mum and at that point should it happen, you need to intervene. If the chick stays out it will die of hypothermia, or get injured or killed by mum trying to get it where it should be.
If you have to move a chick, do not pick it up from above. Slide your hand underneath the chick taking great care that you do not damage it's legs. Usually you can get the chick to clamber onto your open palm, that's how you should lift them.
You will need to lift mum with the other hand enough to put the chick under her rear end, but not directly under her keel bone.
Unless such an emergency should happen you should not attempt to handle the chicks until they are fully mobile and out of the nest, tempting though it may be.