Sudden need to gain weight?

Im 24 weeks now. 3 weeks ago, i had this strong, strong urge to eat, and man i did. I gain 2-3 pounds a week for 3 weeks!!I was up all night eating and eating. I didn’t gain much weight in my 1st trimester i had the same appetite, So did my body try to gain needed weight? This is weird! I went from 145 to 152, in 3 weeks!