Why Do I have a Hard time with physical touch and compliments?

Hi, so I have questions and I don't know the answer everything I find so far doesn't quite capture my question so I want to write it out and maybe see if someone could help me figure it out.

So, I have a really hard time physically touching someone and receiving compliments. Like, in terms of physical touch, I do like it, but it can actually feel so nice that it can hurt, even things like hugs, kisses, and things like that. It feels like almost an overstimulation problem but I haven't ever had these problems in the past I have no sensitivity to light, sound, or literally anything else touching me. I have been in a combat sport for most of my life and when people hit me or are just pushing or playing it doesn't impact me one way or another. But when people physically touch me in a way that feels nice (and not in even an explicit way, like hand holding, hugs, etc) it feels very nice and is EXTREMELY foreign and will actually start to hurt and make me physically start crying. I feel awful because I cannot explain to others that it isn't anything they are doing wrong and that yes it does feel fine/nice but at the same time, there is a duality where it will start to hurt a lot ( I think emotional pain? it is so intense that it feels like the area actually starts hurting). I will say that I have never been in a romantic relationship of any kind, and for large portions of my life would have extremely limited contact with people outside my family (and another note, this issue does not happen with anyone in my family) this problem has only recently been brought to my attention as I am now in University and have started talking and interacting with new friends and people all the time.

On a similar note, I have the same problem with compliments and things like that. If people do nice things for me or say nice things about me, my first reaction is to completely deflect (which I don't feel is actually uncommon) but if they do not immediately stop it can actually make me feel like I am in physical pain, like I want to take a knife down through my stomach open it up, and just give them my insides because I literally want to get the pain out and I have nothing else to offer them. This doesn't have to be big things, like when people have bought me cups of tea or something and I cannot immediately pay them back (I do have one friend who has unintentionally really helped me with this because she will say things like 'I'll let you get the next one' which even if it isn't true, makes the pain go away a lot easier). But it's the same kind of pain.

I don't know what is wrong with me, but I know if I start crying every time someone is nice to me/ or has a positive physical interaction with me, they will start to get tired of dealing with that reaction whether it is intentional or not. I wouldn't blame them either, I get tired of being that person and I'm the one that's causing it/in pain.

Has anyone else dealt with this? What is going on? does anyone have any kind of scientific research that would help me to better understand myself on this front? Thank you in advance to anyone reading/ feedback