Said things I didn't mean to my boyfriend

I'm 19 (turn 20 in a few weeks.) Ever since I trurned 18, anytime I'm on my period, and a few days before it starts, my emotions do a full 360. I'm super emotional and cry at things that I wouldn't cry at. A song can come on and I'll just start balling out tears for no reason. 
Last night, I literally texted my boyfriend I wanted to "end whatever we have" out of nowhere. I was mad for no reason tbh. He said  "hell no, and that I have lost my damn mind" and he said the sweetest things after and ended up calling me asking what was wrong. I didn't even know what to say. All I said was "I just don't want to get hurt" I made him so mad that he hung up. After 5 minutes I burst into tears and called him saying I didn't mean anything I said. I told him I was on my period, idk why I'm acting like this. Then he smiled and was like no wonder. You get like this every time, I love you. We made up and everything's good but I just woke up in the middle of the night feeling so guilty. (Can you believe I was dreaming about food? Lmao) anyways... Like why the hell was I breaking up with him?? (Over text lmao 😭) I feel terrible because he has like two exams in the morning & I don't want him to end up breaking up with me because I'm a distraction. Lmao am I just overthinking??? 
 
He treats me like a princess, I love him and never want to lose him. (I told him this last night after everything). 
My emotions are just crazyyyy. Especially the first day of my period. Is anyone else's PMS as bad as mine? I promise I'm not crazy lol I just get over emotional and over think too much when I start. Nobody's up right now so I'm just sharing this here. lol