Weight gain?

So almost 4 weeks ago I was 206 lbs and now I’m 211 lbs, I’m 5’5” and this is my first pregnancy-21 weeks along. How is everyone maintaining their weight? Is it normal to gain weight this far along? My friends and family look at me and say “ well I don’t know what you’re talking about, it doesn’t look like you’ve put on any weight in any certain areas so it’s hard to tell”. I’m trying my best to keep my weight balanced but I’m having troubles. Help me