Perfectly normal behaviour, icemaiden, and, yes, you're right about the dominant bit. They'll soon establish which it is, my guess being the female.
But ultimately, you are their pack leader, not either of them. Their little "dominance" struggle can only relate to their position in YOUR pack!
The fighting aspect, even the snarling and growling, is natural and is acceptable up to a point. Establishing dominance is one thing, but outright bullying is not acceptable and, should it happen, must be stamped out right away by you. They must realise that play-fighting, as with human children, is okay, but overstepping the mark will not be tolerated by you.
They don't need you to physically punish them, the tone of your voice should leave them in no doubt that not only have they done wrong, but you are the one who decides what's right and what isn't. Ignoring them for a while after you've told them off is also an effective method of driving home your authority and they'll come to respect and love you for it. And try not to feel guilty, as many of us do, because if you don't impose your authority they'll sense that as a weakness and will challenge your leadership within the pack. That's when problems will occur. Firm but fair, that's my motto with my mutts.
The best of luck, and most of all: have loads of fun!