Normal feelings???

My boyfriend of 8 months are having troubles. First, the sex isn’t like it use to be. It’s quick and I don’t get off anymore. Idk what happened it used to be mind blowing now it’s just... ehhh. Second, everytime im on my period i want to break up with him. It feels like he doesn’t make time to be with me and when he does he just so plain. And finally, we’ve already spoke about breaking up before we go to college so idk if any of this has to with that. I need advice ASAP