Vitamin d deficiency and gas, bloating.

I was diagnosed with high cholesterol (ldl 153) and low vitamin d (less than 10, normal is 75-110) and b12 was 320 rest (cbc, liver and kidney profile, thyroid) was normal. for vitamin d i was given d3 60k tablets once in a week and antacids in morning daily whuch made my symptoms (dizziness, pain in knee, brain fog) better. After 3 week dose in forth week i again started feeling dizzy and started having gas problem and bloated stomach with flatulence and nausea when i weak little tight belt or car seat belt for ling time and pain at the lower end right side of rib and muscle cramps. I researched in internet and got to know that recent researches says that magnesium is very important for D3 absorption. Can magnesium be the reason? Which supplement i should go for? Kindly help me.