It sounds to me like it's mastitis. Well, the red boob and soreness does. When I get it, I get the red spot on my boob, which is hot and sore to touch. I also get hugely high fevers and flu like symptoms, like headache, aches joints, lethargy, runny nose. I have never had vomiting with it though. Maybe you've had a bug and masititis? Is bub feeding well? Feed him and drain the breast well, when you feed him try to have his chin on the red spot to massage it. A heat pack can help too, I like to have a shower with the shower head on the sore spot. You can take paracetomol and ibuprofen to help with the pain and any fever you have. Rest up. If it gets hold of you you will feel like you've been run over by an mack truck! It could be a good idea to go to the doc and get a prescription JIC, it can get hold of you quickly and you don't wnat to be feeling like that! Hugs hun. Mastitis sucks!!