when layla got her rabies shot her whole right side behind her "shoulder" swelled and felt very hard. As long as it doen'st seem to hurt him.. and his other activities are normal. i'd just keep my eye on it.. i called my vet about it and he said it was normal... applying heat can help bring the swelling down by brining the blood to the area so if you are really concerned you can try that. hope it helps
