I had traveled and couldn't refill my prednisone prescriptions, what side effects can i expect for not tapering?

Depends: It depends on what you were using the Prednisone for and how long you had taken it. You should talk to your doctor.

Very Dangerous: If you are on more than 5mg per day for more than 2 weeks, you could potentially develop adrenal insufficiency because your adrenal glands have stopped or greatly reduced your body's own production of Hydrocortisone in response to taking oral prednisone.If you stop Prednisone suddenly, could potentially develop headache, dropped blood pressure, nausea, loss of consciousness, coma, death...Avoid it.