what is wrong here

hi

i have these two plants that were recently placed indoor, they have been outside for about 2 months and were fed with biobizz. i constructed a 2x600 flower room. the temps are in mid 20s and humidity is between 40-50. lights are air-cooled so i dont think heat is the problem. i have ordered a ph meter which hasn't arrived yet.
i read thru tons of threads and think there might be a N def or maybe Ca def. im not sure. they are in their 3rd week of flowering and being fed with hesi nutes at half the dosage. they were flushed prior to switching the nutes. so here are the pics. the strain is chronic. this is my 1st attempt at indoor so i need some help.
please be kind and tell me what you think

I don't know much about Hesi nutes but it definately looks like a phosphorus or magnesium deficiency. It's hard to tell from the pics, what type of soil are you using?

plain potting soil mixed with perlite. was thinking a lockout might be happening, not sure tho. havent received the ph meter to test the run of water yet. it is getting worse everyday.

update:

i realized that i have been underfeeding them (was scared to burn em) and have upped the dosage. I heard that chronic is quite the needy plant. It is now the end of the third week of flowering. i was wondering if the plants are maturing as they should, the buds are starting to show but i think they might be a bit small. what is your opinion?