My puppy pitbull is 13 weeks old. I received him 2 days ago and today I took him to get his first ever worm shot. I know I know not good, but it wasn't on me. He's not showing any symtoms of what I've read about. He is breathing excessivly, mainly while he's sleeping, and he's been doing quite a bit today. My guts telling me its the vaccine killing the worms and its just a tummy ache. Someone please help!