Ok. I'm 99% sure that I'm overreacting, which I tend to do with my babies. Today, I took my 5 month old Manx and 4 month old long haired tuxedo into the vet. They are neutered and spayed, have had their rabies and are otherwise healthy. Today I brought them in to get their shots. The ones they received are the upper respiratory vaccine(URVC) and feline leukemia vaccine. After they got home, they seemed normal. However, they both started acting very lethargic a few hours later. They have both been drinking plenty of water, but neither seem to have an appetite. Also, neither is responding to playful attempts. Seeing as they are both having near-identical symptoms, it seems like its ok. I'm hoping this is normal with vaccines, but that 1% of uncertainty is driving me crazy. .