What Causes Missed Periods Since 5 Months At The Age Of 40?

hi, im 40 yrs old now ,50 kls and 5'2" height,missing period 5 months keeps me worried, i cant sleep i made 2 times pregnancy test it was negative then 2 weeks ago i had blood spots when i only urinate d blood goes out but if not urinating no blood going out.I had history of this ovarian cysts from Dec 2008 til April 2009 i took Belara pills at night then i stopped for 7 months but always monitored ds by my OBY monthly, after 2 months it was Feb and March 2010 it stopped my period so see doc again and inject to come d blood but never come so i tranfered doc he gave me DIAPHAGE for 1 month and by august and sept it stopped again.So he gave me Norlevo and now ds my problem from February til now. im becoming fat im worried too much since my stomach big but i did test it was negative. im taking belara 2 months ds time when i saw blood spots.i need your help doctor, i cant sleep very well with ds problem.i want baby more.thanks in advance