Is it dangerous to accidentally swallow a broken piece of tooth? and how long until i know i'll be okay?

Broken tooth: The broken piece should pass without a problem. Call your dentist to have that broken tooth evaluated and treated.

Not usually: Although it might be possible that a sharp tooth or bone fragment might cause difficulties, I have personally never seen or heard of it happening In my 50 years as a practicing dentist. In the absence of any pain or symptoms, I would not worry too much about it.