Gastroesophageal Reflux can cause you to regurgitate alcohol from your stomach into your mouth, exaggerating the result of a breath test, but if there's no alcohol in your stomach it won't result in a positive breath alcohol test.

If you were actually in a hypoglycemic attack, diabetic ketoacidosis can occur, and the resulting ketones and acetones in your breath can create a false positive on a breath test, with false results reported as high as .06.

If you wear dentures or other appliances in your mouth, alcohol-based mouthwash can become trapped behind them and can cause a false positive.

But you're making us guess, and that makes it seem like you're fishing for excuses rather than explanations. Why did they give you the breath test?