Same as the first poster said, I've always heard it only lasts a week. You really shouldn't be going through much of physical withdrawal because you are still getting your nicotine. But, there will be a lot of mental which is what I'm experiencing right now on my 3rd day. I know there's other stuff in cigarettes we're addicted to so that's probably what we're feeling, just hang in there.
I smoked a pack and a half a day, today is my third day smoke free, and I just have the occasional craving and need for a cigarette but no physical withdrawals at all because of vaping. I'm not discounting what you're saying as everyone is different, but I do know if you do have light withdrawals and bad cravings it only lasts for about a week so I just keep looking forward to every new day.
Like someone else said, as soon as that craving comes i just start vaping away and I slowly forget about the craving. Hang in there, I know you can do it!