Nicotine
A nicotine craving may be short even when quitting feels long
A craving can feel permanent while you are inside it. The whole quitting process is long; one individual urge is often much shorter.
What HSE says
Cravings can begin around 30 minutes after the last cigarette, often peak in frequency around days 2 to 3, and individual cravings usually pass in 3 to 5 minutes.
Use a very short interval
During a sharp urge, five or ten minutes can be enough to watch the intensity change.
One short craving is not the whole withdrawal
Repeated cravings and other symptoms can continue for weeks and usually improve gradually.
Use the tool: choose a realistic next interval, return and answer honestly. A NO does not erase previous choices. The timer is not a substitute for medical treatment.
Sources and further reading