The phenomena is called a laryngospasm. It can happen if you inhale an insect while sleeping. Or a bit of debris such as foam from a disintegrating pillow. Usually there is a history of asthma as a co-factor.
You are probably experiencing sleep apnea. The muscles in the throat relax during sleep and if there is enough pressure around the throat this may lead to an obstruction of the respiratory pathway. This causes snoring or even pauses in breathing. This form of sleep apnea is called obstructive sleep apnea. People may experience this occationally, for example if they have an infection in the throat such as a cold. It should be more of a concern if it is chronic, maybe happening many times each night. If so it can be treated and as mentioned above you should talk to a doctor about it as it can affect your health.
No, but I would say it is not a good thing. If this happens frequently, I would sure see a doctor, they might sign you up for a sleep test at a sleep center.