A drag event happens between two touch events.
What you can do is to delay a touch action waiting for drag, if there is no drag after some frames or seconds, do something just for touch.
If on drag mode and a touch even happens, it may be a release and drag must stop.
Is more easy if you just wait for touch release, if you didn't got a drag event before release, it was a tap (this is useful if you don't have tap&hold actions).
Always check touch index too, you don't want weird multi touch response.