Chickenpox weakness. Left arm and leg.

I got chickenpox in November ... before that i used to work 10 hours daily and 3 hours workout daily .. after chickenpox .. i got digestive issue doctor said its gerd .. after one month .. got pain in left arm and left leg ... and severe headache .. brain fog ... i got checked my vitamin b12 was 40 and d3 was 15 .. i got injections of b12 and took neurobion forte for several months .. its been 10 months ... im having headache while i work drive or concentrate .. i cant workout .. i have shoulder pains .... don't know whats the problem as i had to leave my job due to headaches .. i gained almost 15 kg of weight .. when i do workout i get heaviness my head and sensations in my left arm and leg .. i have pain in foot palm .. before chickenpox everything was fine .. please any one can help .. i had my brain mri it's fine