Hey you! A friend of mine had this same situation - she made sure to eat only protein the night before and the morning of. Maybe a little bit of sugar/carb. I was told my whole pg whoa this baby is huge. I did gain quite a bit during the last trimester after gaining very little the rest of the time. The baby was a fine size 6lb 11oz granted 3 weeks early!
Good luck passing the 2nd test!