Hey man, every sing Auto I have grown just loves 'cal-mag', it's like they can't get enough for something haha. Based on what you are showing looks like 'cal-mag' but also, seems a bit early on in the life of the plant, to show those kinds of symptoms, based on what I've seen with mine. I would stick to 10ml 'cal-mag' or so per gallon of water moving forward, since like I said before, Auto's just love this stuff!
For the spots though, I would verify the PH going into the soil isn't too high or low, and honestly if that looks good, I would just ride it out till you started to see the spots worsen.... fingers crossed they don't!
Is this the first time growing this strain/pheno?
Happy Growing! 👊