Outdoor grow deficiency?

I have an organically grown plant started from seed. I am using Fox farm dry amendments, and compost teas as my main nutrients. This plant looked beautifully perfect about 2 weeks ago, then it started preflowering I thought maybe from the heat we are in a heat wave right now 90+ every day. Then it seemed like over night it started getting small brown spots on the top leaves, I did some research and I thought maybe calcium or magnesium, so I top dressed with some Epsom salt and lime. The following 2 days the plant shot up a bunch of new growth, but it seems like the spots are getting worse! This is only my 2nd year growing so I have not experienced many problems, please help!