Brief Answer:
you need to get clinically examined and investigated thoroughly ..

Detailed Answer:
Hello XXXXXXX Welcome to HCM,
I've gone through your query and understand your concern,

First of all, you should note that unsupervised intake of any medications (even multivitamins and supplements) is not at all recommended, so please get yourself checked at first..

These symptoms are not necessarily to be due to vitamin deficiency, specially since it's being persistent for few months now..even inadequate intake of supplementation can also cause this along with several other causes..

If there's any tingling sensation down the legs, pain over lower back along with the weakness and numbness, then that needs to be checked too..

I'd suggest a visit to your nearest physician/ Internal medicine specialist for a detailed clinical check-up along with a few relevant investigations (eg. CBC, Electrolytes, Vit-B12 & Vit-D3 level, Renal function test, recheck FBS and PPBS level- I've checked your previous levels were in normal range but that was 6 months back) in this regards..

Management will be entirely based on these investigation results along with clinical findings..

Let me know how you stay in the due course..any further queries are most welcome..

Take Care
Kind Regards

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