Can this happen from a ph deficiency?

Is this a lack of nitrogen? My plant's leaves are starting to fade to yellow. It started at the lowest leaves then worked its way up. I tried giving it full strength grow big but it didn't take it very well. I saw some nute burn starting to happen and flushed the shit out of it.

What's going on here though? I haven't had a ph meter this whole time until yesterday, so I the water I flushed it with was phed finally.

Should I maybe try to give it Grow Big at half strength? What is your guys' thoughts on this I could use some help here.

Check the PH of your water. I am having a similar problem, lowest leaves started getting yellowish looking and some got some light brown spots. Mine im pretty sure was PH lockout, it was too high. I ordered a PH meter but haven't fixed it yet. I also thought mine was nute burn but it was not, and niether is yours. I can almost guaruntee it's your ph being too high. Find a PH tester ASAP and fix it.

The yellowing is normal. How far along are they in flowering?

like 3 and a half weeks only. this is definitely not normal. all the leaves are dying and falling off slowly. Its killing me to see this happen.

Well for 3 and a half weeks, that is a little early for yellowing. What watering/feeding regime are you using?