I think if you've been taking vitamins already that could explain it. Prenatals help your hair grow much faster than before and your scalp could be sore from hair growing much quicker than usual.
It could be from changes in your hormone levels, that would be my best guess. If you wear your hair up a lot that could cause your scalp to be sore too.
well its more like its tender rather than sore
I've had my head go numb but not sore really unless I have had my hair up for too long or something
Mine never got sore but it got itchy from the extra vitamins from the prenatal vitamin making it grow and every once in a while felt like things were crawling underneath the scalp. Sorry can't help but ill give ya a bump!!