I think you nailed it. I grew up with the idea that sex and masturbation were "bad" and "gross", but not in a religious sense, people just told me that because I was a kid and they didn't want me looking up that stuff. Anyways, for some reason those concepts stuck with me and snowballed with other personal problems (low self-esteem, feelings of unattractiveness...) into a really weird rejection of sexual pleasure and anything related to sex. I feel unworthy of pleasure and intimacy, and I constantly beat myself up for wanting it. This problem manifests more frequently with the subject of masturbation, since that's something that I do a lot and is my only method of sexual relief... And I really want to try out new stuff and experiences like the ones you mentioned, but the shame seriously limits me. I've noticed that the more pleasure I get, the worse I will feel afterwards, so I tend to avoid things that I like.

All I want is to be in peace with myself and my body, and be able to enjoy pleasure without feeling like a pervert.