Hi my kitten is 11 weeks old on Monday. I had him at the vet just over a week ago for his first set of injections. I've noticed today roughly at his left shoulder there is a soft pea sized lump. It doesn't bother him when I touch it. If I lift his scruff up the lump moves with it. He's eating/drinking, normal pees and poos and full of energy and curiosity. Could this be from the first injection site?