Totally normal.
As is the black crud you'll cough up.
Everyone who has quit smoking goes through the same thing, even people who don't vape. It's your lungs and throat healing. As the tar is removed from your lungs, the newly exposed tissue is sensitive and easily irritated. The good part is that it's only temporary. The more your lungs clear out and the more they heal the less irritation you'll have, and it really doesn't take very long before you're no longer bothered by it.