They MAY be making a new queen, or they may be desperately attempting it with some worker eggs... From when you see larvae they should be capped in four days. From when they are capped they should emerge in 8 days. If they are drone eggs they will tear down the cells before that happens. If they are eggs from a fertile queen you should have a laying queen in about two weeks after she emerges. Yes, the first one out will kill the rest.