I've been vaping for about a year now and I started out with 12mg liquid and now I'm at 24mg. The problem is after vaping for awhile I'll start to get a headache right around my temples and they'll bulge a little is it to much nicotine or am I vaping to much? Because I feel like I need to vape and then I get a headache after like 6 drags. Thanks in advance!