healthy pregnancy

Hi . I am a first time mum. Just wanna ask how do we keep our pregnancy healthy? Haven't been brave enough to stand on weighing scale since I got pregnant. I am currently 5 weeks pregnant and I felt that gain weight significantly due to food cravings. I felt very nauseated as well and eating helps me to relieve my nausea. Although my husband keep telling me I didn't put on weight, but I know I did. Thanks in advance.