I think it is definately possible to be a victim of your own selfishness. You may not be an innocent victim, but you can still be a victim.
If you are so selfish that no one wants to be your friend, you will probably lead a very lonely life.
If you are so selfish that you never help others, as has already been pointed out, then it is likely others will not help you.
These actions as well as others will make you a victim of your own selfishness because you will suffer to some degree and the suffering is as a result of your selfishness.
So, yes, you can be a victim of your own selfishness. One doesn't need to be an innocent party to be a victim. We often think of victims as innocent, but as Dawn pointed out, that isn't a necessary component to being a victim.
I think there is a balance between them both. If there wasn't selfish people where would the generous ones be? I am a firm believer that everything has a meaning to it and a balance to it. For instance good and evil or this case selfish and generous. I would much prefer the generous person but a person is the way they are for a reason. We can't deny them their right to be free willed. In my opinion selfish people work better but generous people are more loved.