How can I politely refuse fingering?

I’m the person who previously asked for advice on how to turn down a second meeting. Thank you for your answers. I’m actually good at giving massages, so I’d love to do lots of that with ○○, but I have sensitive skin, so I’m thinking of saying, “I’m sorry, but my skin is sensitive. I’ll give you a massage instead.” Now, getting to the main point: Some men keep fingering me persistently for over 30 minutes, which becomes extremely painful. To be blunt, it also makes me more prone to bladder infections, and I’m having trouble because of it. When it gets too persistent, I pull the man’s fingers out myself, but quite often they react as if to say, “Huh? Why?”... Is there a way to bring things to an end at an appropriate point? I feel that, during the first meeting, it would be a disadvantage to give the impression that I’m too experienced with men, so I generally go along with what my partner wants. For the second or third meeting, would it be better to take the lead by saying, “This time, I’ll take the initiative,” or should I redirect him to another area that feels good to me? Other than fingering, I don’t particularly dislike things like oral sex or 69. I’d like to refuse this without hurting his impression of me, if possible.