Take a look at the pinned topics in beginner forum, specifically regarding cycling. This way you will get an idea about cycling, and new tank syndrome. Also please look at fishless cycling.
Adding more fish at this point, could harm the ones you have because of the added ammonia, so my best advice to you is to create a new post, once you have read about the cycling, and explain your situation in the beginner forum, you can always refer to this post.
When you decide to write the new post give as much info as you can, tank size, inhabitants, how long it has been running.
If you don't have it yet, get a liquid testing kit, not the strips, to measure ammonia, nitrites and nitrates, you will see the importance of this after you read the pinned artichles I referred to above.
Sorry I can't be of more help. but am not as experienced as most people here, and I myself made mistakes in the beginning because of bad advice from LFS.