deficiency? grow conditions? whats wrong with my babys!

i planted 3 lemon haze plants on oct 4, they had purple lines going down the stem from the first day they sprouted. i wasnt worried about it till i transfered them into bigger pots (bout 2.5 gal) and the stems tured very dark purple within first 2 days <- day 20, very undergrown and dark purple stems. i added 2 more lights and 2 of them got a couple tiny purple/brownish spots, the next morning they were worse
day 24. but my camera is cheap, the spots are alot darker than they look in these pics.any advice is very apreciated thanks