I'm 19 Years Old. I Was At The Bank And

I'm 19 years old. I was at the bank and I started to feel dizzy, I could hear people talking but it sounded like they were far away, my vision wasn't blurry but it wasn't normal either, I got really tired and told the clerk I just wanted to go to sleep. This happened twice before but when I went to the hospital in 2014 they told me my blood sugar was normal but when I went to the hospital today, my blood sugar was 149 and they said last time I was there it was high then too. She said that I might have pre- diabetes but not for sure. Can you help me?