protection period question

How do you know when your protection period is up?

It lasts for either 10 days (I think, but it might be 7) or until you get to rank 4 (3rd Baron)

Its 7 days I think and today is my 7th day. I was just wondering if there was some way to know down to the minute when its over or if you just have to guess.

There's no way to know for sure, unfortunately. People will tend to be eager about it and discussing it in chat near and after the protection period is over, however.