ohhh i feel that. i hope i'm understanding properly, and i'm sorry if this is unhelpful
i tend to put things like that off if at all possible, but i must stress how critically important they can be, and weathering dysphoria is better than the alternative of not knowing if anything is wrong. when i have to go for examinations or tests, it helps a lot to have the typical things like earbuds, comfort items like a stress ball you can squeeze if you have anxiety and such, and a support person you trust (not that they necessarily have to be in the room with you if you're uncomfortable, but just to know they're right in the waiting room and will be there for you if you need them). also, doctors should respect the ways you'd like them to refer to certain body parts as to not cause more dysphoria and will typically use more accommodating language if you tell them to, so i've been told. so communication can lessen the discomfort pretty significantly. one thing that might help if it's related to chest stuffs is mentally reframing it, which i know sounds difficult. men can have health problems in that area, too, so it's important to check regardless of gender !! if the anxiety that sometimes accompanies dysphoria occurs, breathing exercises, counting, grounding techniques, or focusing on things in the room have helped me. lastly, after every difficult appointment i have, i reward myself for being brave, even if it's a small thing like my favorite ice cream that i usually don't get to eat. remind yourself that you're strong and reaffirm that just because people who identify as female have to do these things, so do some nonbinary people and boys, and it doesn't change who you are. i'm not very good at giving advice, i'm truly sorry. i really want to be able to help, but i suck at it