Girls, who has such weight fluctuations? Since pregnancy started, the …

Girls, who has such weight fluctuations? Since pregnancy started, the weight didn't change, suddenly by 19-20 weeks +2600kg. Then plus, then minus 500gr. Yesterday was normal weight, and in the morning +2 kg! I'm sitting on a diet because of sugar, I don't eat sweets and bread. Appetite wasn't there, ate little as if. Swollenness doesn't bother me, I don't have them. Previous pregnancies gained weight gradually. Growth spikes are also in children born, and at 25 weeks my baby is gaining weight... Grams ? I don't understand from where it is like this...