My 11.5 year old Rhodesian Ridgeback threw up and it looks like there are pieces of blood in the vomit. We’ve been giving him bully sticks everyday the last few days and he ate grass yesterday. His weight is normal. He has a healthy appetite. His stools are firm and a normal color. He has no decreased energy. This is the first time this happened but he threw up a few days ago also and it was yellow and foamy. I included a few pictures.