Add new column based on Filtering Pandas Dates

Question

I am trying to add a new column in my data frame based on dates in the date column. As part of some analysis work, I want to map dates that fall in the last 7 days as "Period 2" and the previous 14 days as "Period 1" in my data frame

p2_start_date = df["Date"] > (max(df['Date']) - timedelta(days=7))
p2_end_date   = df["Date"] <= max(df['Date'])
Period_2      = p2_start_date & p2_end_date

p1_start_date = df["Date"] > (max(df['Date']) - timedelta(days=14))
p1_end_date   = df["Date"] < (max(df['Date']) - timedelta(days=7))
Period_1      = p1_start_date & p1_end_date

date_filters = [Period_1, Period_2]

date_filters_values = ['Period 1', 'Period 2']

Then to add my column

df['Period'] = np.select(date_filters, date_filters_values, "-")

So I get the desired output

    date        Period

01/01/2001  Period 1
02/01/2001  Period 1
03/01/2001  Period 1
04/01/2001  Period 1
05/01/2001  Period 1
06/01/2001  Period 1
07/01/2001  Period 1
08/01/2001  Period 2
09/01/2001  Period 2
10/01/2001  Period 2
11/01/2001  Period 2
12/01/2001  Period 2
13/01/2001  Period 2
14/01/2001  Period 2

This is fine as long as there are no missing dates. But the issue is I need the same count of dates that fall into both periods. The above won't work if there are missing dates. For example, if the data frame is missing the 3rd, 4th, 5th, and 6th, will give the below. And that's because the filters are relative to the dates I've set for.

    date        Period

01/01/2001  Period 1
02/01/2001  Period 1
06/01/2001  Period 1
07/01/2001  Period 1
08/01/2001  Period 2
09/01/2001  Period 2
10/01/2001  Period 2
11/01/2001  Period 2
12/01/2001  Period 2
13/01/2001  Period 2
14/01/2001  Period 2

But I'm not sure how to select the dates correctly, I'm not too familiar with Pandas datetime module so apologies for my ignorance but any help is appreciated!