I can't come, or feel much, during sex. Help?

First time asking any sort of sexual question so forgive how awkward I am about the topic, and how awkward I know a lot of my phrasing is. I (22 f) and my girfriend (23 f) were both virgins before we began dating and recently started having sex. My problem is that, for some reason, when she touches me and tries to "get me off" I don't feel much of anything and have never been able to even get close to coming. When I'm mastrubating by myself I can feel stimulation just fine (though seemingly not much) and can come. From what I can tell, I'm just in general not very sensitive to any sexual touch (whether from myself or her), internal stimulation does nothing for me, my nipples also dont really feel any stimulation, and clitoral stimulation is kinda 50/50 for me- from what I've tried (vibrators, oral, etc.) dont really do anything for me. It bothers me that I'm not able to feel much- I'd like ro know if there's anything I can do about that? Anything that would increase my sensitivity? I've had arousal oils and the like recommended to me but I dont know how legit those are, or if they even do anything. Any advice, please?