Not able to breathe after being choked by saliva. i feel saliva go down the wrong tube, then bam! i was like drowning :( is this dangerous?

Somewhat: If you are healthy, you'll be ok. If you have a medical condition that causes this to happen, you can develop a lung infection &/or inflammation. Inhaling solid material such as peanuts or chunks of meat can be deadly. Read about the heimlich maneuver.

May happen: Occasionally people may choke on saliva when they swallow wrong, but this usually clears quickly when it is only saliva and does not contain particulate material which can easily obstruct airways and cause asphyxiation. It usually is not particularly dangerous with liquids alone, but this depends on volume.