Yeah I am 9 weeks tomorrow and when I don't eat enough, the same thing happens to me. (Although sometimes when I do eat it all comes up again). A nurse told me that the pregnant stomach likes to be half full all the time, so keep snacking - and bland foods are often best even if it feels like they're not as healthy. I heard that one girl pretty much lived on ginger ale (remember to get the kind with real ginger, in the healthy section of the store) and saltines throughout her first trimester and her doctor said she was fine. Luckily the umbilical cord is still forming at this point and most of baby's nutrition comes from you later.
Make sure you are eating even if it's just crackers you need to be keeping at least something in your system
Stomach acid. Eat something
Ew acid is the worst to throw up I hate it! But completely normal!
It's just all the acid from the bottom of your stomach.. it's perfectly normal I had it all the time x