Keep an eye on it, don't rush it. I would check nutrients regularly, i checked mine every 2 days for a little while to make sure they didn't hit 0, but if you have .03 and that high of nitrate without dosing it directly, i would say you are pretty good.
I let my dinos take over my entire tank thinking it was normal before I realized. Patience and steady slow reaction to it after it got way the hell out of hand, and it was gone after about 2 months.
I would say, just observe, and keep the idea of nothing happens overnight paramount, and just make sure your livestock is good.
Also, at one month, definitely probably just diatoms, i didn't realize it was only 1 month. They may cover your entire tank, but they start the micro biome food chain in your tank, and will dissipate with good care. Making sure your water is from a good source, preferably RODI, and don't panic when it looks super ugly. I promise the patience game pays off.
Also, if you don't have a CUC, start picking some out, you're going to want it soon.