[BlueAbyss]

Read read READ before doing anything in this hobby, mistakes can be very expensive. Quick lesson on the nitrogen cycle, ammonia is excreted by fish converted to nitrite then nitrate by bacteria, and from there can be turned into nitrogen gas by bacteria, picked up by alga (which can also consume ammonia directly), or removed in water changes. If you have ammonia today and nothing is producing more, it will go down pretty quickly, being converted to nitrite and then nitrate (and becoming less toxic at each conversion).

Reef tanks reach sort of an equilibrium after a change is made (ie: adding a new fish, more light, etc.) and takes a little while to reach that equilibrium. It sounds to me like you did too much too fast. Move slowly and do a lot of research before you add livestock... specially with delicate creatures like anemones (as an example).