The pain aspect is something you should address. First with your partner if their technique can be changed, and second with a few doctors.
This one is like a layer cake - maybe you’re ace, maybe there is emotional context (that could be entirely unrelated to your current situation) that causes physical discomfort, or possibly there’s a physical component that your doctor might be able to help you with. Or some combination of all of them, because people are complex.
The pain aspect is something you should address. First with your partner if their technique can be changed, and second with a few doctors. This one is like a layer cake - maybe you’re ace, maybe there is emotional context (that could be entirely unrelated to your current situation) that causes physical discomfort, or possibly there’s a physical component that your doctor might be able to help you with. Or some combination of all of them, because people are complex.
But romantic asexuality is definitely a thing, as is a number of variants within it.