You have high myopia. the mechanism and genetics of high myopia progression are not completely understood. There is an epidemic of myopia world wide especially among Asians. In 20 years projections indicate most people would be myopic unless a prevention is found. You do need to see an eye MD ophthalmologist. High myopia can also be associated with higher rates of glaucoma, cataract and myopic macular degeneration, retinal detachment.