I have this eye issue.. my eyesight's been weakening every time i go to the eye !

I have this eye issue.. my eyesight's been weakening every time i go to the eye doctor..?

any ways to improve this? i've had glasses since 3rd grade (currently in 8th) & i'm at a rather high point right now (about 500, and it's not crystal clear anymore). I just got contacts last december, but i don't think that plays as a factor. Anything i can do to improve my very bad eyesight? I feel i'll be literally blind by 20.

Hello there, as you grow and mature its normal for your eyesight to change as well... whether its better or worse.
In myopia (nearsightedness) it is very common for it to get worse as you get older. This usually levels off around college age (late teens/early twenties). Its just a natural process and there is not much you can do to stop it. Wearing contacts will not make it any worse! Just take good care of your eyes by maintaining a healthy diet. It won't necessarily stop your eyesight from getting worse, but it will keep your eyes healthy which could help a bit.
There are many things that you can ingest that promote eye health like: vitamins A,C,E flaxseed oil, omega fatty acid 3, beta carotene. Take caution when taking these things because taking too much can be harmful.
Reduce the amount of eyestrain you endure by taking breaks while you are on the computer/watching TV. Also protect your eyes by always wearing UV protected eyewear when outside. UV rays are known to cause macular degeneration and cataracts.
Other then that there is not much more you can do.... maybe when your a bit older you may want to consider laser eye surgery. Anyways hope that helps :)