Gestational diabetes ?

I had my 28 weeks glucose test, the results were in normal range but on the higher side, however I went shopping after I was finished with my test and while shopping I got hot, sweaty and dizzy almost fainted, it’s happened a few times during this pregnancy (second), I had to have chocolate and a sugary drink to calm it down. It took about 20 minutes to feel back to normal.

Would this mean I have gestational diabetes?

I don’t see my midwife for another 3 weeks so i can’t discuss this with her.