Questioning if I have OSDD: How do you tell for sure?

@GoldenSystem (I apologize in advance for the long reply) The issue I’m having is that I’ve always been so hyper aware of how I was behaving—like voice, speech patterns, ways of walking or holding myself—it’s hard to tell what comes naturally and what’s been learned. And since I started trying to present as masculine, I’m having to think actively about these things even more. The things that make me think I might be switching are usually subtle and more inside my own mind—like sudden unexplained changes in mood or perspective, sudden increase, decrease, or change in motivation, and some shifts in how I view myself or the world. Sometimes, even though I can’t actually tell a difference, things will somehow appear different or sound different, and a selection of my facial muscles will tense or relax; the best way I can describe it is that it feels like switching gears. Usually this isn’t apparent from the outside since I—or we—are so aware of even subtle mannerisms that I/we don’t allow them to change. There are times, however, when it is a more apparent switch, mostly when I am around certain people. I haven’t found the exact pattern of who, since I do it around some people I know and some people I’ve never met, but I always—no matter how hard I try to fight it or prevent it—do it around customers (I work retail). I could be talking to a coworker, being completely naturally myself, with a customer right next to us overhearing everything, but as soon as they turn to ask me a question I snap into nice-mature-young-woman. I actively try to speak in a more masculine voice, but when I talk to customers I cannot make myself stop sounding feminine. It’s so weird and uncontrollable that when I do it in front of a coworker—like in the situation I just described—once the customer leaves and we go back to our conversation, I feel disoriented and a little embarrassed, usually trying to laugh it off as faking around customers. Although, since I have DPD, this could be explained by me just reverting to old habits around people I’m not comfortable with. The thing that makes me question that is the fact that this isn’t an issue around everyone I don’t know, and I’m not sure why it’s so prominent specifically with customers, since work is one of the places I feel most comfortable. Also, recently, my thoughts have been a lot more jumbled like I’m having more than one train of thought at once. This becomes apparent sometimes when I end up restarting a sentence over and over like I can’t decide how to phrase it (ex: “You know how… It’s like… No, I mean… Okay so… Well the thing is…). I’ve had anxiety for as long as I can remember, but this particular thing had never been a problem until recently. Sorry for the long rant, but I’m wondering if the things I’m describing are actually signs I have alters, or just a combination of stuff brought on by DPD and stuff that I didn’t know are actually completely normal.