Why, Oh Why, Menses

Girl, Lady and Woman have to endure this every month in their life. But some don't have it every month.. should I envy them???
I got my first menses when I was 12 yrs old.. yes, THAT EARLY....when that period of time, most girls have it when they are in secondary school...Throughout my teenage and six years ago, I don't have problems when it comes every month... Only when I reached 30, stomach cramps were there. Not severe, alhamdulilah... its just the feeling of discomfort existed...
It seems that for now, there is different symptoms that I get nearing my menses date.
1) Itchiness on my leg and armpit
2) Always feeling sleepy
3) Frequent urinating
4) Feeling sweaty, especially at thigh area
only recently, I keep getting fast heartbeat, be it in the day or night. It be ok when the menses flow...Know that all of us won't get the same symptoms... But heartbeat? Falls into it too???
Anyway, I did have a check on myself two years ago...hmm.. should do it this year...