This would be a good forum for answering your questions since there are both Libertarians of different types and Objectivists that post here. I refer to my self as either Libertarian or Objectivist, as best suits the context. I consider most Libertarians to be allies of mine on the political level (as long as they are supporting a constitutionally limited government - not anarchy or one of the strange forms of libertarianism like Socialist Libertarian).
But, Ted is correct, you gain no respect when your avatar insults those you are addressing.
Only a small, perhaps tiny portion of those who are Objectivists adhere to the idea that only Rand could call herself that and the others were doomed to be "students of Objectivism." I think that is a complete non-starter.
You say, "I don't mean to offend...." Well, it would be reasonable to suspect that you do mean to offend since you chose an avatar that is flipping the bird at those in front of their monitors, and because you make these statements about Objectivism, and about Rand, that are negative yet you say you are a devoted fan of her writings. It seems more likely that you are trolling for a negative reaction - based upon those two observations.
If you are not, then we'll see the avatar change to something that isn't insulting, and you will give thought to the these simple facts: Objectivism is a set of principles and a person understands them or doesn't, agrees with them or doesn't, and thinks independently or doesn't. Those who understand these principles and agrees with them and thinks independently would never believe that they must think just like someone else - including Rand, and would not look to others to determine what they will call themselves, and would never bow down to anyone else. But we will also hold her in much greater esteem than to call her "just another student."