What Are The Body Changes Women Go Through During Middle Age?

I would like to know what do 40 year old women go through , meaning what are things that can change within there bodies , i am 40 i seem to have alot of things going on with my body i weigh usually about 9 stone, but i have lost alot of weight down to 8 stone my height is about 5.2 my medical history is that i have never had a normal pregnancy, forcepts, cascerian, and vuntose , i have mild asthma , last attack i had was last year. Usually i am well and fit but lately i feel i have no energy, seem to get sick offten, had a cut finger, had a bang to the head caused cussion , and now have a stomach bug. I am visiting a doctor tomorrow to have a full check up i am due for a cervical smear. If you could email me a response it would be appreciated , i work full time , and some times above, i have 3 children and a husband that works away nearly every week.