Air bubbles under dogs skin?

i TOOK MY DOG TO THE EMERGENCY VET LAST NIGHT HE LOOKED LIKE HE WAS SWOLLEN HIS WHOLE BODY WAS HUGE AND HE IS A LITTLE TERRIER SO NEEDLESS O SAY IT FREAKED ME OUT BAD ANY WAY TO MY QUESTION THE VET SAID IT WAS AIR UNDER THE SKIN AND HE WAS FINE THEY PULLED SOME OF IT OUT WITH A NEEDLE BUT I WANTED TO KNOW HOW BEST TO DEAL WITH HIM AT HOME DO I JUST LET HIM DO HIS NORMAL THING OR DO I KEEP HIM IMMOBILE?