There is nothing unusual at all about your situation - your birds are only just beginning to lay, so their systems are just figuring out how to produce an egg - this means that they may lay in starts and stops - also, not all the birds will begin to lay at the same time. Just as with humans, each bird will mature at her own pace - the expected beginning of lay is just an estimate/average and varies from breed to breed. Their first eggs will be small - they will get larger as they get further into their laying cycle. Leave their vents alone and don't chase them off the nests, soon enough you'll have more eggs than you know what to do with.
As an example, in our current flock of pullets we have 15 birds - GLW, SLW, EE, Light Brahma and BO. Our first egg was a BO that came 2-3 weeks ago -- since that time others have reached the point of lay and begun to lay, but we are still only at 11 of 15 actively laying. and we get anywhere from 7-11 eggs on any given day.
For comparison, the egg on the right is store bought, the one on the left is from our red sexlink and the middle is from one of our Easter Eggers.
