There are certain strains of HPV that you can get orally, usually the higher risk kind that cause cancer. The reason your OBGYN said it was okay is probably because oral cancers aren't common (though if you smoke or are a heavy drinker, that will absolutely increase your chances), so if you do get oral HPV, it probably won't do much of anything and you'd never even know.
How long ago was he with the other woman? How long ago did he have the warts? I ask because HPV is not a lifelong infection. Most people clear the virus from their bodies within 2 years, and the longer he goes without symptoms, the less of a chance he has of transmitting it.
The incubation period for HPV can be several months. This is the time from infection to symptoms, so if this is all recent, your pap today may be normal, but your next one may not be. Stay really current on your paps if this is all really recent.
I know this is all very scary, but it's estimated that about 90% of us will have HPV at least once in our lifetimes. Most experts consider this an inevitability for sexually active people. You're going to be okay, whatever happens.