Call 911 and leave the phone off the hook
The dispatcher will send someone to help even if they hear no talking on the other end.
Try to cough up the object
If you can cough or make any sound, your airway is not completely blocked. Try clearing the object with forceful coughing. Do not try to drink anything as this can compound the problem.
Perform the Self-Heimlich
This is essentially the same Heimlich maneuver that you would perform on another person, but instead you will perform it on yourself. Make a fist with one hand and put the thumb side between your belly button and rib cage. Place your other hand on top of that. Push as hard as you can in a quick motion straight into your abdomen. This will put pressure on the bottom of your diaphragm, which will compress your lungs and force the remaining air to push up through your trachea, hopefully with enough force to dislodge the object.
Seek medical help
Once you dislodge the obstruction, you should go to the emergency room or urgent care. The Heimlich maneuver can cause internal damage and you should be examined for any complications. The doctor will also check your lungs to be sure you have not aspirated any foreign substance into your lungs which could cause infection or other complications.
Do this please