Broody is a hormone thingy. It is normal. These are pullets, not yet hens, and have not settled into a laying schedule. While it is not common for pullets to set after only laying a few eggs, it happens (and these pullets are not good choice for actually staying on the nest for the 21 days--IF you wanted setters, so should not be allowed "setting" privileges.) IF indeed they ARE in a setting mode so early, removal from ANY nesting place is a way to upset the hormones and get them back to laying. (food, water, bare floor!) Most pullets and hens will prefer to lay in a nest that already has an egg or eggs. (wouldn't you like to crawl into a warm bed, if a choice?) And so, even setting hens with fertile eggs, will sometimes move to another nest after getting off to feed, drink, and depositing a big smelly poop, (and lose their hatch) so should have a private place to set and hatch. So-- collect your eggs several times a day so that there is no happy setting of the pullets. (Setting hens do not lay--it is a resting time from production of those lovely eggs.) Some breeds of poultry are "good" setters and HENS will set after a small clutch is layed--12-15 eggs or so. PULLETS, may lay up to 30-40 eggs before setting, so they are not yet on a laying schedule. Mixing pullets and hens can be a reason for mixed hormone stimulation???? While many folks have no probelms, I never do it! Means extra pens, if you keep your hens, but it makes happy chickens, living with their own friends of same age group. Your birds are doubtless perfectly normal--has nothing to do with not having roosters. Proper feed and housing, will get them on a schedule==enjoy them!