birth control weight gain

Hi! So my bf and i were looking at pictures the other day and he said how good i look now. I was like what are you talking about? And he explained to me which i see in the pictures now from the summer i look so much bigger. During that time i was on birth control. I have been off since august but havent changed the number on the scale. Im just wondering what the reason is for such a change in the pictures. I do feel healthier now being off of it.