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"I dont know the PH. Havent received PH meter yet."
Cool. That's good because we now know your problem, and it's easy to fix.
Don't transplant until you get your ph meter. Get distilled water from the pharmacy - it's ph is 7.0, close to the 6.8 max that we want. Most unbalanced ph with fertilizer is low since fertilizers are usually acidic, the 7.0 will bring your root ball up slightly.
Flush with distilled water now, 1x volume of your pot should be fine. Water will pour out the bottom of the pots, do over a bucket or sink. This will balance the ph of the root ball so the plants can absorb a full range of nutrients again. When you get your ph meter feed as normal.
Your leaves already have damage which may get worse, don't worry about it. Those lower leaves would fall off by the time you get to flower anyway. Everything is fine.
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