Gestational Diabetes

Anyone that was diagnosed with gestational diabetes after taking the 3 hr test have any noticeable symptoms ? I failed my 1 hr by almost 20 mg, and have to take the 3 hr one. I just feel like I have it because I get so nauseous and lightheaded whenever I eat carbs or a lot of sugar. Could be a coincidence but just wondering if anyone has had the same symptoms and had gd?