4 Weeks into aquarium cycle

I'm a bit stressed and every week I get my water tested. As of last Friday my water was still 0 amonia, 0 chlorine, 0 nitrite and 0 nitrate, PH 7.7, hardness 100, alkalinity 120. I keep my temp at around 76 degrees. I bought 3 danios at the end of the first week to help move the cycle along, but still water is perfect. I used/use a product called "Cycle" when I first set up the aquarium and have followed directions and treat the water once each week. Internet sources (not always reliable, I know) say my water is already cycled since I've used that product. I've since added 5 glowlight tetras last week, and now 2 juli corycats and a few oto sucker fish yesterday. All fish doing fine with no signs of stress, except for one oto who died within hours of bringing him home. I bought 3, can't find 1 but see the other regularly.

Did I add fish too quickly? Has my cycle really been completed? :22_yikes:

Update as of this afternoon. I just had my water tested about an hour ago and am at 0 amonia, 0 nitrite, and a trace of nitrate!!! Woohoo! Still going to watch it though and will do a 50% water change next weekend if everything is still going well. I might have to do a water change sooner, but will watch it closely.