Hey Shelby, nothing is wrong with the vaccine you squirted into the cap, just cut the cap in half and suck it back out with the needle attached to the syringe. Not like it's dirty or anything. I've done that a couple times, no big deal, just suck it back out. I wouldn't want you wasting money and buying another shot for her. With the relapse thing, it's always possible, but it is preventable, unless his immune system is somehow deficient one day and he gets another. Just be sure to finish any medication if the vet gives you any for him. If you caught it early, usually they can just shake it. Hopefully it will be a good immune-builder if he shakes it on his own rather than with meds. Good luck to ya