What Causes Numbness On The Lower Arms?

Hi, I am a 29yo male. I am a non smoker, but my parents smoke and I had been a passive smoker.

I had the following:

1.I have numbness on my lower arms (worse on the left arms) – from elbow to fingers, but no tingling sensation.
2.It pains a lot when I pinched my palm
3.Frequent Headache
4. I can see my vein on my left hand (near the wrist between the thumb and index finger pulsating) when i feel numb.
The numbness a few days ago ( around 4-5 days ago)

Does anyone has any idea what is it?

Thank you :)