Recently it seems like little bits of chippings came out of some of my teeth. what does this mean?

Many possibilities: This condition may involve many factors from decayed teeth to nighttime clenching/grinding. Seek professional evaluation to help determine the specific reasons in your case.

May be grinding : During periods of stress or in response to a malocclusion(bad bite) or other issues, you may tend to grind your teeth especially at night. You can do a lot of damage. See a dentist to make sure your teeth and gums are healthy. You may need to have a custom made night guard. This will protect your teeth and jaws.

I saw a patient: Recently with a similar complaint. His condition was due to oral hygiene neglect. The chips were tartar or calculus that were breaking off as some of his teeth were loosening (bone loss). Just offering another response. The best solution is to go to a dentist for a checkup to see what the cause is and be treated for it. Hope this helps.