if I ate a tiny piece of lamb, for sure less then a kezayis am I fleishig?
Answer:
The halachah is that a person has to wait after eating meat, even an amount that is smaller than a kezayis.
Authorities dispute the halachah after tasting meat without swallowing (please see here). However, if meat is swallowed, however small the amount, a person does become fleishig.
Best wishes.
