Just Curious

Is it normal for pms symptoms to change? Normally I have really bad cramps and back aches leading up to my period, but right now there very mild. Of course there will be periods where there stronger but that doesn't last very long. I'll also have a lot of discharge and right now it's very minimal. According to eve, my period should be starting in a couple of day. I know it's not always accurate but it's usually pretty close. I'm 38, so I never expected my pms symptoms to change. I have recently taken a pregnancy test and it came back negative. My periods where regular until last June then after that my periods became very irregular. And in June I had all my regular pms symptoms before my period started.