Get a new list of time between each item in list of dates

So I’ve got a list of dates. These are times when a person ate food.

I’d like to calculate how long they fasted, so I need to get the length of time between each two dates.

Like if the list is
Mon 0800
Mon 0900
Mon 1300
Mon 1330
Tue 0800
then my new list of fasting times would be