Acne can be so awful...emotionally especially. And when it happens on your face it's even worse because that's where everyone looks. I can empathize. I've dealt with acne on my face my whole adult life and I'm old now. Sometimes meds clear it up and sometimes they don't. I'm on a regime (below) that has cleared up almost all of it (I had horrid cystic acne before) but I still get 1-2 small inflammed whiteheads on my cheeks that my derm thinks is rosacea.
You're still young so hopefully you'll outgrow it. My son outgrew the worst of his acne in his mid-20's but he still gets a pimple here and there and he's in his 30's now.
I'm sharing this because I want to give you some thoughts about how to handle your acne. Like I said hopefully you will outgrow yours but if you're unlucky and keep on having it...just remember that life goes on. It does. And you can decide if you want it to cripple you or if you'll just get on with life.
I'm also a "stressy" person. This is mostly due to never knowing how my skin is going to look. From what you say, I think my skin was much worse than yours but even now that it's better I stress over even tiny whiteheads thinking they're going to blossom into full-face acne like I had before (terrifying). This may be happening to you because of how your back was...and now your face is breaking out. The mind goes into "what if" mode and worry sets in.
Despite how awful my skin was I went ahead and did presentations...rose to the top of my career and was head of a large department. Did I say my skin was awful? It was. I had cystic acne like you had on your back. I was on meds that helped. I took accutane twice. I got glimpses of how life could be for people with clear skin --- never having to worry. But that was short-lived and I was back to the usual inflammed face. Yet despite all this I made friends. I gave seminars. And being a woman it was even harder because all the magazines show perfectly clear skin and give advice...like as if if you still have acne you must not be washing your face or doing the right thing. Very embarrasing. But I went on and lived life...married, had kids, and now am still in a very public job.
Since I've been dealing with acne for so long I'm sure I have "Acne PTSD" (post-traumatic stress disorder). It takes very little to trigger my feelings of shame regarding my skin and also feelings of panic. I know what it is. And it sounds like you are beginning to develop some of that because your facial acne is not that bad and yet you are feeling ashamed and poorly about yourself and it is getting in the way of living life fully.
My recommendation is that you talk with a counselor about this. Be honest with the counselor and talk about how your acne is affecting you, especially when you have to give presentations. It will help! Besides dealing with the self-image issue it will also help you in feeling better about presentations.
Talking with friends might help but a therapist or professional counselor is trained to help with this kind of issue...and to help you cope better.
Here's two other scenarios of people I know who have coped much more successfully with acne than I have. One is my son who had horrid acne...much worse than yours and even mine. He got over the worst of it with age but was still breaking out. He purposely decided to ignore it emotionally. He uses some acne products (tea tree shampoos and body wash, salicylic acid facial wash, etc.) but doesn't freak out when he breaks out...he just goes on with his life. He travels, got his master's degree and is now a therapist. He once told me that he just accepts it as part of who he is and when he breaks out he just goes ahead with life.
The other person is my nephew who is in his early 20's. He is still coping with horrid cystic acne. He is on meds but they just clear it up a little bit. I saw him yesterday. He had inflammed acne all over the side of his face and some lesions on the front. He leaves it alone...ignores it and goes on with life. Funny thing is I noticed it for a few minutes and then forgot he had it. He was smiling, happy and fully engaged with everyone. He has a beautiful girlfriend (clear skin) who adores him. Here's this guy with terrible acne but he's not letting it get in the way of his life. I'm sure he's bothered by it but he's not going to let it stop him from living fully.
Honestly, I am still crippled by my acne at times but then I remember that it is all in my head. Yes, this is a horrid disease...but it is just a disease like other diseases. We cope, we go on, we find ways to feel better even in the worst of it.
Hopefully you will get lots of support here. You can private message me if you want. You will be okay!