I’m a FTM my baby is 1 week old today;

My little one gave me a huge scare today :( he was nursing and all of a sudden threw up and it had a lot of blood mixed with my milk!! Like clots. And I freaked out and took him to the ER! They said he looks perfectly fine and it was the one and only time he has done it. So they think that my nipples were bleeding a lot when I was nursing because he nurses for so long that he ingested a lot of my blood! 😭 I had a heart attack but apparently that happens sometimes and I’m just happy he is okay 😩 but it also seems like too much blood to have just come from my nipples bleeding and cracking?? Like he even digested some of it and his poop was almost a blackish yellow color. He is still sleeping, wet diapers are good, he is a happy baby, nurses a lot and can be calmed down a bit. The ER doctor said my breasts are red or hot to the touch so he doesn’t think I have mastitis or anything just bleeding from my nipples? Should I still be concerned?

I just wanted to know if this has happened to any other moms??