Create one more field using if condition which tells which data is older that 5 mins,10 mins and 15 mins. Use these values like flags.
Call this field as Duration.
Then you can use this field in UI also as drop down. In this case a simple expression will do work for you since automatic association will be created in the back end.
You can use of Alternate Measure in the same chart. It will allow user to select in the same chart.
Another way of using Qlik Branch extension.
Create buttons for
1) Last 5 minutes
2) Last 10 minutes
3) Last 30 minutes using variables.
Use that variable in to change measure according to selected button