It is a yeast
infection. A yeast
infection can be under your nails, on your skin
, throat, stomach, etc. Thrush is VERY painful, and you would know if you had it. It looks a lot like a yeast-like infection in general, but a lot more painful.
You need to see an ear, nose, and throat doctor and have a culture done to see what it is. Your boyfriend may have carried some yeast on him that passed into your mouth. Get checked and let us all know what he/she said.
Hope you feel better soon!