What do you guys do to improve your self concept?

I am very successful in my career, but I feel like socially I am a huge oversharer, trust way too easily, am insecure in my abilities/talents/self worth, and I really feel like I’m such a fool in social settings. I’m trying to change my self concept based on the idea of how we feel about ourselves is reflected back to us. Every time I walk into a group at work, all I can feel is everyone thinks “oh the fool is here”, I hate it so much. I’m working on being less of an oversharer and not letting shitty coworkers rile me up, but it’s really been doing a number on my self concept. Any advice/tips would be helpful!

Edit: more context - I am a doctor finishing up residency, I will be moving to a new state for fellowship in June. I am great with patients and my superiors, but I’m in a girl highly male dominated field with very little women in my program and have literally no friends in my tiny town. One of my coresidents goes out of his way to make me the butt of the joke, ironically this is the one I over shared with in the past because his wife and I had so many similarities and got along really well so I thought he could be trusted and I was really just looking for a friend. I always take his jokes in stride so I don’t get perceived as someone who takes things too seriously, and that has allowed him to really push my buttons because I essentially have no boundaries so that I’m not perceived as a bitch. I regret this but I’ll never see these people again in a few months so I’m happy about that. I’ve realized I say a lot of dumb stuff and over share to fill in silence or get closer to people or to vent about life to people I think I can trust. This has almost always backfired, I am way too trusting of people. Other things that may be contributing - I used to view myself as incredibly ugly (elementary, middle, some of high school), I’ve improved a lot physically since then and when I look in the mirror I love what I see and get regular compliments from strangers, but my inner perception that I’m very ugly is still there and unless I’m in front of a mirror, that’s my perception of myself.