It definitely sounds like you have some level of vaginismus.
Every woman is different, and different types of penetration can elicit different responses in your body.
You are able to have intercourse, which is great, but you still struggle with other types of penetration.
I would start with a dilation program, the more confident you can become in your body with penetration, the easier it will be to translate that to other types of penetration, like a tampon or gyn exam.
Seeking a Pelvic Floor Physical Therapist could also be very helpful.
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