Heather,
Don't panic yet, everything's OK. and welcome to TFP!
The Nature 2 system causes problems in a couple of ways; (a) it adds silver and copper to your water via the mineral pack (so don't install the mineral pack), (b) the Z-tabs are trichlor tabs, and eventually will cause your pool to become overstabilized if you don't periodically replace water, and (c) recommend a FC level that, when combined with the increasing level of stabilizer in the pool, doesn't properly sanitize the pool. This is why we don't recommend their use. In fact, several members here on the forum (myself included) are former N2/pool frog/aquasmarte users, and experienced the problems listed above.
The BBB method we advocate is actually more about learning how to test and manage your water chemistry, and then using chemicals that can be found in your local grocery store for the most part to maintain your water.
So, first things first. Go ahead and take the Z-tabs out, and start adding a small bottle of unscented bleach every evening at dusk to get some chlorine going in your pool. You'll want to slowly add it in front of a return so it mixes in well. Next, click on the "Pool School" button at the top right of the page and start reading the articles there, especially the ones under "Getting started", and "pool chemistry". Third, take a sample of water to a pool store and ask them to test it for you. Don't buy anything that they suggest, just tell them you'll be back later. Post the results here. Fourth, seriously consider purchasing a good test kit. It will be the best investment you'll make for your pool. We recommend either the TF100 sold by a member here on the site, or the Taylor K-2006, which can also be found online and in some retail stores.
One last housekeeping item - please add your pool specs and equipment to your signature, as it helps the members here help you by being able to read what size pool you have, filter, etc. You can add a signature by clicking on the "User Control Panel" link near the top left of the page, click on "Profile", and then click on "Edit Signature".