Hmmm, it really does sound like it's like this b/c of the increased blood flow. Mine was very sensitive when I was pg too, and I didn't enjoy DTD b/c I was always really dry down there and after DTD it would burn so much I was in tears. That dryness stayed months after DS arrived and even now it's just not the same
I'd mention it to your midwive, it doesn't hurt to have a second opinion
GL with the rest of your pg hun!