It means that they are angry with you. That's absolutely it.
Now, what you must do is figure out how much you respect that person's opinion. If it's someone who's opinion you value, then you may wish to consider that they are telling you that your ego is a bit bloated.
The opposite could also be true - a bloated ego well recognizes a threat to it's self, and so it tries at times to "project" it's own sickness onto another by saying such things as "get over yourself."