Brown dots and leaves curling up help!!

First grow and I'm on week 6 of buding stage. I just wanted to know is some one could tell me if its normal for the plant to start to get brown dots and leaves starting curling at the tips. Not all leaves are like that just 3-4 are. Buds look amazing and nothing wrong with them. Is that normal? I will put up a pic as soon as I get home.

Anyone? here is a pic of one of the leaves other look like it but not as bad as this one.

It's very hard to tell under LED lights.

Here is a pic with out the light. Only like 3-5 leaves out or all of them are like that.

Looks like a calcium deficiency to me. What's your soil mix? Are you using RO water or regular tap?

I have been feeding plant water for past week. I use rodi water and past month kinda cut back on fox farm nutrients Cuz I was started to nutrient burn on the leaves. I must of cut back to much. I'm using fox farm soil Ocean Forest