This may be "laryngospasm' when the laryngial opening close reflexly.
One major cause is acid reflux; acidic fluid from stomach regurgitated and irritating the larynx.
You didn't mention your age or if you have been taking any medication earlier. For ex. some medication taken for high blood pressure may cause this.
Another is 'adult whooping cough', which of course, is rare. But so is such laryngospasm.
If you don't feel better in a few days, you may have to visit the ENT again.
My sister has whooping cough. her children have been confirmed blood tests as whooping cough and now she has developed very scary laryngospasm. Her throat completely closes and she can't get air in. After waiting 8 hours at A+E a student doctor told her it was reflux!!! Don't they train doctors anymore? Clearly this is a side effect of the whooping cough not a reflux problem. She has to pick her children up from school and the young doctor told her if she passes out then so be it she wont die. I fear for the NHS and the lack of care.
I am an adult in my forties with children who currently have whooping cough. We are in the beginning of our second month; the cough is far less severe than it was for my children, but still persists nevertheless. I have developed laryngospasm (never had it before) and can only imagine that it is a result of whooping cough - very scary! However, I would like to highly recommend a mouth spray (from Boots) called 'Expert Dental'. It puts the moisture straight back into the mouth which is critical if you want to avoid laryngospasm and you can use it as often as you need. My daughter who is nine also uses it and it helps tremendously, especially at night when waking up and cannot speak for lack of moisture. You have to ask for it at the pharmacy counter and it isn't cheap - cost me £6. Also, if you develop laryngospasm (as I have done) you must sleep with at least two pillows and on your side to avoid an attack in the night. Have the spray by your bed and use it before sleep and if you wake in the night - it really does help me not to panic when I can't cough or talk. There are also other oral moisturisers on the market called synthetic saliva, but I haven't tried them yet as happy with Expert Dental. I am also giving you a link to a website that will give you a technique to alleviate a laryngospasm attack when it happens - takes some practice and thought, but it does work and they use it in surgery where a patient having a tube put down their throat goes into a spasm. Try not to panic (easier said I know) but now I have this technique to hand as well as the mouth spray, it makes life far less scary and I can get on with my day for my children. Good luck and hope it works. The following is the link I told you about.