you are not messed up! it sounds like these experience messed with your sexuality...or the normal development of how sexuality unfolds....because you were so young when you had these experiences. i dont know the parameters of what would fall under abuse but it definitely affected you....you may have enjoyed it...even little kids who are molested by parents carry shame because parts of them enjoyed it....a natural body response to sexual stimulation......but it sounds like there was more to it emotionally...maybe you felt pressured? are you currently seeing a therapist who you can talk this out with? but definetely dont feel like you are messed up. you are not!