I got an inhaler a few years ago from an urgent care doc. Later, when I went in for something else I asked if I could get refill on that inhaler because of this throat tightening thing (the inhaler did seem to help, even if it was really just lessening panic). The doctor, who took more time discussing symptoms with me, didn't think I had asthma...also I noticed muscle relaxants (for other pain) alleviated the "asthma"....so likely all muscular and stress related. I don't know the direct link or how it's triggered but I know I've been intubated several times since birth (oxygen, stomach pumping).
I don't notice it anymore, so therapy probably helped that part. Though now it's just a little constricted often and it feels hard to get words out, so something I hope can still get better. The scary throat tightening is gone though. In therapy I acted on some coughing and gagging reflexes...feeling like something was stuck in there. My therapist encouraged me to see what would help and was supportive of my gagging sounds and coughing (I didn't barf, but it felt like that sort of!).
Good if you have a sense of your own throat thing. Until you get back to therapy can you find more ways to express with your voice? Or type something here and read it out loud, loud and clear? I don't know, but know you're not alone (it is scary but less scary when I know I'm not dying...but the tightening is involuntary, so good to find any way I can help express, cough, relax, whatever I need).
P.S. my profile pic here is sort of a weird drawing I made of my throat!...what I imagine it's like in there on a good day.