Finally finished my pomodoro 
Button with the bell is a “one minute alarm”. Without this button I wouldn’t have come across some rendering problems. I think I learned a lot with this project
Your timer is technically adding an extra second between when the timer hits zero and then switches to either break or session. For example, when the session hits 0:00, that technically is 1:00 for the break. Your timer does the following:
Session
0:03
0:02
0:01
0:00
1:00 - Break
0:59
0:58
But should actually do one of these:
Session
0:03
0:02
0:01
0:00 - Break
0:59
0:58
OR
Session
0:03
0:02
0:01
1:00 - Break
0:59
0:58