My brother has a black eye and a lot of blood in the white of his eye from being punched?

Question: He got punched or elbowed or something at a concert on accident about a week ago. He had blood in his eye, which actually looks sort of like a blood blister, and doesn’t appear to be going away. He also got a black eye out of it. He says he can see fine out of it, but I’m just wondering if this will affect his vision in the future. Should we see a doctor about it?