Hi, I’ve Female I’ve Had Cancer Twice , Last In

Hi, I’ve female I’ve had cancer twice , last in 2012, Chemo, breast.
Ive been having serious sweating at night, it gets worse & worse. Started 14 yrs ago Chemo didn’t affect it much if I remember right. But it’s 100% worse than 2 years ago.
My potassium very low - per dr, taking meds for it now since 2 months ago. I still have cramps on legs & feet daily tho.
Then I just got diagnosed out with diabetes, why? 2 months ago. From same blood test.
Could this be cancer again?
I’m 50 yrs old