What Causes Scanty Bleeding?

I believe that i am suffering from scanty bleeding. I have been taking femulen the mini pill for 20 years on and off and this has been ongoing for a little while but not to the point i have been concerned by it, however i have recently been ill and am currently undergoing tests for brusing easy. Is this dangerous and should i be worried, i am only 37 ? can it be cured and would you recoomend i stop taking the pill ?