It's Her First Time Having Sex. She Got Delayed And

It's her first time having sex. She got delayed and we were panicking if ever she is pregnant or not. I told her i really did withdrawal and for 5 years of my sex life i just do withdrawal. We did pregnancy test one night and it showed negative. The next morning another pt was taken and it showed negative. ng and there's something weird one time we had unprotected sex before taking pregnancy test, twice it smelled like blood

Question:
What are the chances that she is pregnant?
Is the cause of her delay due to hormonal change due to 1st time sex(if it is true)?
Is withdrawal safe after the 1st round when you pee and clean it 1st?