I have a new colleague on my team- she started few wks ago- she has been doing some of the work that i used to do -dealings with massive customers- but may be doing other more intense things in future but isnt as yet. She is currently getting a higher pay grade than me and is currently on holiday and my manager is expecting me to do the work that she has been doing but at my rate and not her higher one. Is this right? Am i just being dramatic lol? Any advise would be much appreciated.