Help me save this lanky female sativa!

I am the new owner of some type of heavy sativa. I was in about a gallon pot and was vegging outside, showed sex and just continued trying to grow. My friends mom couldn't care for it properly and gave it to me. I transplanted it and put it in a 5 gal pot it was rootbound badly. I gave it a good feeding of ff big bloom and superthrive along with miracle grow. The leaves were a little yellow. Its about a foot tall very lanky and petite only 3 leaves instead of 5. Any suggestions to help me save this plant? It is now on a 24/0 cycles with my indicas under a 400w hps. I was wanting to go into flower on the first of the month with my indicas. How long would it take for this plant to rebound?

if plant was really stretched when transplanting yuu should have planted it deeper in pot

good luck
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