need some reassurance.

So my man & I we having a makeout session and long story short he put his dick in me for a few strokes. He did not cum inside me or anything but I heard the risk of pre cum. He did not ejaculate before so apparently there would be no Sperm from the pre cum ? According to google. I know my chances are really low, im just the type to worry a lot. I know I'll use protection in the future. It was just " in the moment" and it seemed safe. Since all he did was a few strokes then out , I ended up blowing him after so then he actually cummed because we stopped the stroking in me because we didn't wanna risk anything. He says I don't have to worry and I'm 100% fine. But I still always over think. And I don't want the stress to actually delay my period for when it's due around a week.