Is there any way to see own NMC balance?
No, not yet, but WK said he'll try to do something about that.
I've not yet confirmed my NMC address.
As far as I know, as long as you do not put in an NMC address, you do not earn any NMC, the pool keeps them. That's how it can afford to do 105% PPS for NMC, by splitting the earnings of all the miners who do not claim it.