Porque?

Too early harvest, wrong environment, could be many things .... Lower temps, good and powerful lightning, feed schedule and not early harvest ;)))) are main things to follow for good nug . Some strains are better , some phenotype of same strain aka any other sister seed, could be more potent, bulky, even grow with different structure .... Many things to consider when you grow. Always supply good air flow too, buds need wind, they hope to be polinated and bulk up in that hope if given good care. Good luck ! P.s. anyway, it's your own grow and it's the best in the world for you ! Be proud still ! Improve with time, don't panic !