What Causes Delayed Period With Stomach Pain,nausea And Hot Flushes?

hi, I m about a week late for my period but for the last 5 days I have been having these terrible stomach pains that I d usually have a day before I start my period. I also get the terrible urge to go to the bathroom as if I m suffering from diarrhoea but I can t go along with terrible nausea, and the hot flushes it lasts between a few mins to roughly an hour throughout the day, sometimes wake up at night feeling this way. Today I started with the shakes amd cold sweats. Any information regarding as to what this is would be great. Thank you