Pregnancy helped me in a few ways, how to get that back

Maybe the wrong place for this question but I (24F) was pregnant with twins. While pregnant I had no dandruff, could go a long time without washing my hair and didn’t have to shave while pregnant. I’m now 15 weeks postpartum and my dandruff is worse than ever before, my hair can’t go two days without being washed or else it is just horrendous and I have to shave again. Is there a supplement or vitamin that will get me those things back again?