It isn't recommended to use an apv (advanced personal vaporizer) along with another form of nicotine delivery such as a patch or nic gum. An overdose of nicotine can be pretty severe, including side effects like headaches, nausea, elevated heart rate/blood pressure and you just shouldn't risk it.
Any science behind this advice? For years they "advised" not to use patches and smokes together, and then dropped the B.S. and acknowledged that there was no evidence that using both was bad.
I think the risk of "overdose" is really low. Try to vape. Use other means if necessary. If you get too much nicotine you'll know it (tear off the patch, quit vaping (duh)), but I don't believe there's a great risk of overdosing.
Just an observation, not a medical opinion.
Good luck!