13 weeks and 2 days and haven’t gained weight😔

I’ve always had a small frame when I was about 7 weeks I was 84 and I lost 5 pounds because of my nausea and throwing up it was so bad and I didn’t have an appetite for anything well I’m still 79 pounds and I’m 4’9 the doctor wasn’t really concerned cause I’m tiny cause it wasn’t a dramatic weight loss and she gave me tips on how to gain the weight back but I just felt so sick and couldn’t take big portions so I did small portions but still wasn’t gaining the weight where I want to be. Every appointment baby is growing and all is well this is my first baby and I just wanna make sure I’m not doing anything wrong nausea is getting better so hopefully i should gain the weight back?