What are the chances of me going blind when im older? Or legally blind?

I'm 16, i have astigmatism, in kindergarten was when i first had to wear gles, I only had to wear them off/on though, When i went out to play i could take them off, in 1st grade i wore them constantly, at 13 i got contacts. Idk what my vision is without gles but i think it's 20/375 in one eye and 20/275 in the other? my contacts box says SPH -3.75 and CYL -2.75 so i just multiplied it by 100 thinking that what it means but idk. Anyway, what are the chances of me going blind or legally blind when i'm older? My corrected vision (with gles or contacts) is 20/30 in one eye and 20/50 in the other, and that's the best they can get it i believe.