I have what I originally thought was a mosquito bite (they love me and I am always getting bitten and I do react badly sometimes). But it seems to be spreading into a rash.
It actually reminds me of when I had mastitis ( only with DC1 and that breast got abcesses anf had to be surgically cut open and drained, 8 years ago). But DC2 is nearly 3 and stopped bfing at 4 months old. The rash bit is quite tender to touch and it does feel a bit warm. And it seems to be spreading towards the armpit area 
The spot bit does get a little itchy which is why I thought it was a mozzie bite.
But of course I have been googling and I am now thinking the worst.
Cause for concern and a trip to the doctor?