Rapid weight gain?

Okay I need some advice! I feel like a whale! The first photo was just now at 5 weeks compared to the second photo at 3 and a half weeks. I've put
On about 5 pounds and it's not just
My stomach but hips also. I've been starving lately so I've been eating more than I should but I do crossfit 4 days a week and run on the weekends. I'm also a teacher so I'm on my feet walking all day, I feel like I should not be getting a stomach or gaining this much weight so quickly. Any advice, tips, reasons?