Weight gain

So I recently found out I was pregnant. My last period ended on Jan 30th, it was only 5 days long. I took a pregnancy test and somehow I just assumed I was pregnant. I’m apparently around 4-5 weeks and I know most people don’t know they’re pregnant until they’re at least 6 weeks so I just assumed I had to be like 6-8 weeks pregnant. And now I’m even more confused because I’ve had recent weight gain that seems not normal to me. I always put it off as I’m not as active as I used to be and I eat worse ever since quarantine and covid, because I don’t go out I just stay home. But it’s really starting to make me feel self conscious. Am I crazy or is weight gain usual in early pregnancy?