Talk to Internal Medicine on Weekness Low Blood Pressure

weekness no energy,dizziness(blurry vision),numbness,irregular heartbeat,feeling tired all the time sexually down,blood pressure remains at 100/60, all tests cbc vit d sugar fasting calcium level are clear hb is also 14.2 Alhamdullilah vit d level 75 i am using indrop d after 15 days also using vitrum multivitamins from 4 months but found not effective kindly any medical speacilist please guide me should i go for b12? i was captain of my school football team never get into any disease except typhoid 3 years ago