after period

I know it's weird but does anyone experience this or know why it happens....
So I posted on here a while ago about not having a period for 4 months. Literally the next day I got it😩 but now I've been off my period for a day I'm feeling extremely emotional,literally I want to be on my own and sit and cry at everything, now I don't know if it's because I've spend the last 3 odd weeks with my boyfriend and I'm missing him or is it hormones??
I'm just very curious 

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