Stopwatch with registered timestamp at push of a button

Hi again.

I am trying to find a stopwatch function that register times on a click on a button in a specific cell.
Only thing I find when I am google stopwatch is a start, stop, reset function.

In this case, I want to first reset the timer (If it not only restored allready)
And then, when I push "Start" then stopwatch will start...
Then when I click Reg. 1 the timestamp from the stopwatch is going to be saved to B5
The stopwatch is still going....
Then when I click Reg. 2 the timestamp from the stopwatch is going to be saved to B8
And when I click stop the timestamp from the stopwatch is going to be saved to B11 and the stopwatch is going to stop.

Se attached file...


If there is a more easy way to do this then the example I find, please do tell me...
The file I attached is from google and copy paste with some minor change from me.

Thanks in advance