Hi. Welcome to AA.
I have few questions:
How long have you had your tank? Have you cycled it properly? When you said "very newly cycled tank", how new? I am asking because properly cycled tank will have the levels: Ammonia=0ppm, Nitrite=0ppm, and Nitrate = 5-40ppm. And you can normally get this levels at the end of the cycle which is around 4 weeks.
Do you have a Master kit? If you don't, get one as soon as you can. API Freshwater Master kit is my favorite, better and accurate readings than the strips.
My bet is, you just had an ammonia bloom. It is quite normal when you are first cycling your tank. It will clear away after a few days. But do check the levels of the ammonia. Levels are important when you are cycling. That is, assuming, if you are really not done with cycling.