I was pregnant and gained 20 kg. Then they didn't go away after that, …

I was pregnant and gained 20 kg. Then they didn't go away after that, I weighed 90 kg for another year. I walked like that, my height was 174, I was fat, couldn't afford clothes I liked. Then I lost 28 kg and walked at 62 kg until this pregnancy. So now I'm... (crying) I'm gaining weight too quickly, 73 kg. What should I do? Can I start a diet that doesn't harm the baby? I'm very afraid that I will get fat again ???????????