How to create multiple if statements with meeting specific criterias such as date ranges based off of TODAY()'s date

I've created a spreadsheet and would like to create an IF statement that will populate the cell with text (low, medium, high) if a certain criteria is met. For example, I'm tracking sub-assemblies that are due from our outsourcing vendors based off of specific due dates.

Condition 1: If an assembly is due within 7 days of today's date, then I want the cell to populate with the text "Low". Condition 2: If an assembly is due within 3 days from today's date, then I want the cell to populate with the text "Medium". Condition 3: If an assembly is due today, then I want the cell to populate with the text "High". Here is what I have, but I'm only coming up with a "FALSE" return. =IF(C155>TODAY()+7,"LOW",IF(C155>TODAY()+3,"MEDIUM",IF(C155=TODAY(),"HIGH")))