MY 4 MONTH OLD ITALIAN GREYHOUND HAS A SMALL KNOT

MY 4 MONTH OLD ITALIAN GREYHOUND HAS A SMALL KNOT ON THE INSIDE OF THE RIGHT KNEE RIGHT UNDERNEATH THE SKIN NOT ATTACHED TO THE MUSCLE. SHE HAS ANOTHER THAT FEELS LIKE ITS ATTACHED TO A MUSCLE OF LOWER INTESTINE. BROUGHT HER TO THE VET HE STUCK A NEEDLE IN THE ONE BEHIND HER KNEE AND NO INFECTIOUS MATERIAL CAME OUT JUST BLOOD. HE THINKS THE OTHER PUPPY MAY HAVE BITTEN HER. HE BASICALLY TOLD ME TO WATCH BOTH BUMPS AND MAKE SURE THEY DON'T GET ANY BIGGER AND BRING HER BACK IN 30 DAYS. SHOULD I BE CONCERNED?"