Excel Trigger on change help

I have a lot to learn with Excel, so here's what I need if anyone can help me.

For work, I upkeep a excel spreadsheet for project status, but also have a history with finished projects. 

I basically want to trigger a change in a cell on one sheet, from N to Y (for example), and it will take the information on that row, and store it to another sheet at the top. 

Bonus pts: I need also to have a cell on the second sheet that will fill the timestamp of when I did the trigger.

Any resources or help?