Need clues

Tota • Vet 🥼 ! LA girl ! 👧🏻 1st time pregnant 🤰! EDD June ! Dog Mommy 🐶🐶 🐶

I’m panicking coz I felt a small lump , size of a pimple under the skin ( on the chest just below the collar bone) of my 6.5 month old baby ? I will see his doctor this week but am so scared and really worrying. It is invisible but u can feel when touched and my baby has no reaction to it