I am being tested for cushings disease, recently done dex test, took pill at 11pm, had blood drawn 8 am next morning, level 13.5 ug/dl did i suppress?

It sounds like you: followed the instructions properly: you took 1 mg of dexamethasone at the proper time (11 pm) and your blood was sampled correctly the next morning at 8 am. A normal test should suppress to less than 5 micrograms/deciliter. So it looks like you did not suppress.Discuss with your Endocrinologist to exclude medication interference, etc,and to plan further testing for Cushing's syndrome/other things