blood in vomiting during 11th week of pregnancy . is
Hello and welcome,
Vomiting is fairly common in early pregnancy (first trimester - 1st 12 weeks), but blood in the vomit is not. It may be that because of having a lot of vomiting, there has been irritation or a tear. But it needs to be sorted out as to how much bleeding and ways to stop it.
So yes, I would advise to be on the safe side and go in to be seen now.