Help me with my Polaris 380

[Pools Scare Me]

I have a polaris 380 that has worked ok until now. I went to turn the boster pump on and it makes an awful noise much louder that usual. It almost sounds like it is not getting water or something. I have absolutely no idea what is worong. I turnned it off for fear of it overheating. What should I do now???

Any help what so ever would be appreciated beacuse my pool company severly overcharges me and they are the only people near me.