Not sure if fermenting correctly

I am brewing my first batch of beer making a light wheat beer. The entire process I believe went smoothly until after a few days I saw no bubbling in the fermentation lock. I realized i never added water to the lock. Will this ruin the beer?

I now added water to the lock and still no bubbling after 12 days, however there is a layer of foam on the top of the beer. The temp is around 67 degrees. Will bubbling occur and when can I begin to bottle??

Welcome to HBT!

The airlock will keep the nasties out even without the liquid so don't worry (though do try and remember in the future, it's an extra layer of security). Also bubbling is not a good indication of fermentation, any leaks in the seal of the bucket or the airlock grommet or bung will let the CO2 escape.

If there is a layer of foam (called krausen) on the beer then it is definitely fermenting properly. Once the krausen has fallen you can check the gravity and see how it's doing. Once it has been stable for 3 days you can bottle the beer.

i'd wait at least 2 weeks before bottling. go ahead and add some water now, but i'm sure it's fine.

How many days exactly has it been fermenting? The about answers are totally correct. However you should have bubbling. I don't think anything is wrong with the beer, but make sure your lids snapped tight. Stand on the dang thing if you need to. I do.

I brewed a wheat a couple of weeks ago that only bubbled for a few days, before it settled down to one bubble every ten minutes or so, and eventually to nothing. So it's probably nothing to worry about -- you may have just had a few days of really active fermentation.

Extra tip: I read somewhere (Palmer's book, probably) that you should fill the airlock with vodka or sanitizer instead of water, to prevent contamination in case of backflow. I use Starsan (food safe at normal concentrations), and fill the airlock with that. The only downside is that with a super-active fermentation, all of the Starsan will bubble away. I need to pick up some vodka.