Hello
The first photo looks a bit like a phosphorus deficiency, especially being the lower leaves on the plant. Double check your nutrient levels and the ph so they're in a healthy range.
If it's affecting just a few leaves keep the faith and keep growing forward. ✌️
If you have a ph tds reader check your runoff ph and ec levels to see where your at. Let them dry out first. Always let them dry between waterings. Cheers friend