i have found a lump behind my 4 year old staffordshire bull terrier's ear which is under her skin and not red and a bit bigger than the size of a pea, she has been feeling down the last few weeks but she's still been eating and still wants to go for her walks. She has had health problems in the past, like having to be spaded because of a really bad infection (she has never been mated) she also gets alot of problems with her anal glands. i will be taking her to the vets on monday for them to check her but i would be very greatful for any advice anyone can give me about what this lump could be.