Will my eyesight progressively get worse?

okay well my eyesight has been on and off for a while lets start in elementary. I was about maybe 8 or 9 years old when i got my eyes checked by an optometrist and he said i had astigmatism and he gave me glasses which made me see things more closer and farther away than they actually were so i never wore them. Then a few years later i went to get my eyes checked again but in a different place called 4 eyes and they told me my left eye only was a bit less than 20 so i was close to 20/20 vision but a bit off on the left eye and that I didn't need the glasses. Now im 14 and my left eye is a bit more blurrier then my right when im looking at objects and print from far away. I am going to the optometrist this week and im probably going to get glasses. But depending on my history with eyesight will my eyesight become worse as the years go by? Im really worried about that happening i mean my parents didn't have nearsightedness only reading glasses and my mom has glaucoma in her eyes because she also has diabetes but none of that runs in her family. My sister has a high case of astigmatism she really needs glasses she wears contacts all the time no one knows where she got the gene for her eyesight from either. On the other hand my other sister has 20/20 vision. Alright sorry for my very long paragraph question.