You should see a doctor. Look for a free clinic in your area. There are several in my small city. Call your local health deptmart or food bank for help finding one if needed.
You could research vocal cord dysfunction (VCD). There are several video clips of breathing techniques on the web. This could be the cause of your difficulty. VCD is a spasm of the vocal cords that can be triggered by many things including crying, singing and laughing.
I hope that helps you and that you find answers soon.
Feel better and have a blessed New Year.