How can I stop overthinking i could get pregnant

(Btw I’m on the combo pill and have never missed a pill) So in the past I’ve had pregnancy scares which made me become such an overly anxious person so I cut sex out of my life until I feel ready. But now when my boyfriend fingers me I overthink I could get pregnant. I make him wash his hands beforehand to be extra safe but I still overthink. I just want to enjoy it but I can’t. I can’t get pregnant from him fingering me while his hands were washed beforehand right?