Funny period question from boyfriends😂😂😂

So last night my BF and I were out playing a game of pool and lately he has been a little horny which I love, because he picks me up and sets me on the pool table and starts to make out with me, but then he asks when my period is over so he can eat me out and I answered, I don't know..like 2 days or so. He comes back saying how don't you know didn't you look down there this morning to check if your still on it. I just started cracking up laughing so hard,😂😂😂😂 because he doesn't know anything about periods. So I tried to explain all the pain we get,but I don't get the pain that normally comes with it , becuase he's asked before why I'm not moody. We are both 19 don't you think a 19 year old guy would know how a period works. well he doesn't. He knows girls wear tarpons but he didn't know why, he thought the blood just sits up there.😂 lol! But I don't blame him for not knowing if I was a guy I wouldn't want to know either!😂