Hi, my 4 months 22 days old baby has a small lump on the left thigh. whenever I apply ice it will be softened, by night it's getting hard.mostly it's painless but occasionally she is feeling sore in that area. we observed this lump after 1 month of her birth. I feel it's due to the injection given at birth. can you please suggest to me on this issue. Is it safe to assume it is due to injection.