We took Vega in Wednesday for her final booster. This evening a lump has developed in her in her scruff. The lump is relatively loose and does not feel very hard, almost like a piece sof fat under her skin. There are no signs of redness or of any type of bites. We took her to the Dog Park for the first time today and she had an absolute blast with her pals that joined us. She had more than her normal amount of energy and the lump or me handling it does not bother her what so ever. So I am comcerned as we noticed this this afternoon. It was not there this morning. So does this sound like a vaccine lump or ????