I know that tomorrow is the day after that or the next day and last night is the night before and so on. However, I am not sure about some other dates such as next Monday, this week and specifically 4 weeks from next Monday.
We can shift from the future in the present to the future in the past, when talking about dates, by substituting 'the following' for 'next', and 'that' for 'this':
Next Monday: the following Monday.
This week: that week.
Four weeks from next Monday: four weeks from the following Monday.
Next year: [during/in] the following year.