I feel like my experience is different from most other's here: I don't remember being in diapers as a baby, don't remember potty training, and I didn't wet the bed as a kid. Sometime around age 7 I remember a sudden curiosity for what a diaper would feel like, and I sneaked an extra from my little sister's room. Tried it on, was too small, promptly took it off and hid it under my bed. For some reason I decided to tell my younger sister (I guess 3 or 4 at the time?) emphasizing that it was a secret, but I overheard her immediately going to tell my parents. They didn't really react, never confronted me about it, but I was thoroughly embarrassed.
Sometime after that, I would make up stories before going to bed about creating machines to force people to wear diapers and become babies, or having this being forced upon myself. Also stories about being sick or hurt in someway and being bedridden with someone I didn't know taking care of me. These stories were calming and comforting, and gave me tingly feelings like I needed to pee, even though I had peed just minutes ago. These stories eventually tapered off around high school/college.
As I began my sexual exploration, these fantasies started to filter back into my conscious thoughts, and I felt extremely guilty about them. I have OCD, anxiety, and dissociation disorder, a job caring for young children (which I love, I've enjoyed childcare since I was old enough to help), and was terrified that I was attracted to children. This became an obsessive thought and I tried to remove those thoughts from the 'sexual' side of my brain.
I have since become more accepting of my little side and comfortable expressing myself with younger 'babyish' clothes. I know now that I was having intrusive thoughts caused by my OCD and I would never knowingly hurt a child or anyone for that matter. It's been extremely difficult coming to this point in my life, but I just got my first package of little clothes yesterday, and my brain feels so much calmer and more grounded than it has in months. This community also has helped me accept that I am not a bad person for liking little things or having sexual thoughts surrounding regression. Refusing to accept and love myself for all it's quirks and idiosyncrasies has caused so much pain and self-loathing in the past, and I'm finally over it. I want to accept my whole self as I am and allow it space to grow.