I have a Dunkelweizen from a Northern Brewer all-grain kit that I brewed and pitched 2 weeks ago. I have one problem, I forgot to aerate before I pitched the yeast. I'm concerned that the yeast will not have enough oxygen to carbonate when I bottle it. I have more yeast I can pitch when I prime(Wyeast 3068), but will that be enough? Will aerating it now give it a bad taste? Any advice would be appreciated!
You should only aerate before the yeast have had a chance to really get going, so that they can consume all of the oxygen that's in suspension. It's really too late now, and will likely result in oxidized flavors. The yeast should be fine for carbonating your beer with simply the priming sugar, though.
The carbonation process occurs due to fermentation of the priming sugar. Fermentation is an anaerobic process, therefore no additional O2 is needed for carbonation to happen. You'll pick some up anyway through simply by racking.
Excess O2 post fermentation will oxidize the beer and create stale flavors as well.