At first, I was kinda worried bc your kiddo was given Rabies on the same day as other vaccines (rabies should be given separately, at least 3wks apart, and given alone)...but then I saw this was all given on Monday, and he sounds like he's doing good
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Hard to say at this point if the lump is permanent (would then be under the umbrella term "vaccinosis") or if it will go away...only time will tell. If it does not go away...you kinda need to approach all future vaccines w/ add'l precautions, esp. bc you don't know which vax this "lump" was caused from.
You may want to phone vet and ask which vax was given in this location...they may have give the other vax above one of the hind legs, so at least then you could figure out which vax is causing this.