May have worms?! worried mom

I recently (about a month ago) adopted a new kitten from a rescue. it took the rescue a long time to get back to me about the the kitten's previous vet records. It turns out he hasn't been dewormed. Which means means he is three months old and I am terrified he has worms. I called and the vet told me to come in and get revolution ( he is about 4 pounds or more) and just deworm him. How long does it take for Revolution to take effect? If I start giving it to him tomorrow will he be okay?

I think it is a few days and they usually ask to be rechecked...

Don't be terrified, it isn't serious (unless enver treated) and it is easy to treat. If he doesn't have diarrhea or loose stool then he's probably fine anyway.