Prediabeties with symptoms of hypoglycemia.?

I had a test run about a month ago H1ac and it showed my average being 121 glucose level or whatever. They said i have high blood sugar but most times it feels really low. I ate a piece of cake not much and i felt fine but then i got cold clammy hands and shakey, my stomach feels like i am going to vomit and i feel like i am trembling. My eyes also hurt and i feel disoriented. How can i be hyperglycemic with the symptoms of hypo.