Counting text occurrences by week

Hello,
I am trying to compare the amount of "OPEN" slots there are in a given week with the amount of items that need to be worked on.
The way I've approaching this so far, with no success, is to assign a given date a week number (using weeknum function). Then tried the countif and sumproduct functions to see how many times the text "OPEN" is associated(in same row) with that week number. Then later compare the number of entry's (in the queue column) with the same week number. So count the number of times OPEN occurs in a given week and compare that with the number of samples created in a given week.

So column A is a chronologic date, column B is a text column containing the text "OPEN" (or some other text) indicating if a sample can be tested in morning on that day. Column C is the same text column indicating if an "OPEN" slot exist on that date in the afternoon on that day. Column D is the date the sample enters the queue and Column E is the sample identifier. I'm trying to see if the number of "OPEN" slots is smaller than the number of samples entering the queue for a given week.
I know my way around a few basic formulas in excel but haven't been able to figure this out. I hope I have explained myself enough for you to help me.
Thanks in advance