Brown spots, high ph?

Little help for a newbie? I have an outdoor grow in a Northern latitude, somewhat sandy soil by a flowing creek. Plant seems basically healthy, but with some brown spots and browning/yellowing on some lower leaves. Soil PH is 7.2, what should i do to get it down? I've been feeding it organic fish fert diluted in water during veg, and have switched to organic bloom fert now that it is blooming. Have I overfertilized, or something else? The brown spots don't seem to be insect damage, I haven't seen any bugs.

Thanks so much!

That plant looks good. What you are seeing is insect damage. A light application of neem or hot pepper wax to the leaf surface will help repel those bugs.

Good news, thanks, I'll do that. Do you think the high PH (7.2 or so) needs fixing?

Well, I'm not seeing any of the problems associated with high pH lock-outs, so I'd say that unless you see deficiency symptoms, you are okay.
Next time you go out and water, you can bring a gallon of water that has been adjusted to pH 6.5-6.8 with cider vinegar- don't add nutes to this solution, as they may interact en route to your site.