Hi, I recently had blood tests showing low levels of Vit B s, Magnesium, underactive thyroid, low DHEA etc. I am a type 1 diabetic but eat pretty good. I had a vit B12 shot at the Doctors office yesterday and felt pretty good. Around 4:00 today I started feeling a crash. Now my muscles are tight and kind of numb. I already took 350 mg of Magnesium. I m getting cramping in my feet. Could it be due to the B12 leaving my system? He just gave me a test dose and said it would be out of my body in a day or two. Am I taking too much Magnesium and not balancing it with other electrolytes? Thanks,