6lbs in one day?!

I drink water constantly, hardly any soda or juice... hardly eat anything but salads, soups, veggies, once in a while eggs for protein, and sometimes a cheese quesadilla with pico de gallo (my craving). Literally this is all I eat Bc everything still makes me sick! How the heck did I gain 6lbs in one day? I've only gained 6 lbs this whole pregnancy until today when apparently that's gone up to 12. I went from 155 yesterday to 161 today 😭 I'm 24 weeks and was so proud I hadn't gained much weight since my last pregnancies I gained 65 the first time and 40 the second. I'm kind of devastated... Didn't want to gain more than 15 the whole pregnancy like my dr wanted...